Remove NaK/Rust dependency, port remaining functionality to native C++

Replace NaK Rust crate and nak_ffi with native C++ implementations:
- Game detection (Steam, Heroic, Bottles), VDF parser, icon extraction
- Prefix symlinks, SLR manager, Steam path detection
- Known games database

Add FUSE VFS optimizations: zero-copy reads via fuse_reply_data,
default_permissions mount option, FUSE_CAP_ASYNC_DIO, FUSE_CAP_EXPIRE_ONLY,
lookup cache parent index, cached mode bits, increased I/O buffer sizes.

Update build system, prefix setup, and various fixes.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

1 files changed, 0 insertions, 259 deletions

diff --git a/libs/nak/src/steam/paths.rs b/libs/nak/src/steam/paths.rs
deleted file mode 100644
index 8ef5013..0000000
--- a/libs/nak/src/steam/paths.rs
+++ /dev/null
@@ -1,259 +0,0 @@
-//! Steam path detection utilities
-
-use std::fs;
-use std::path::PathBuf;
-
-use crate::logging::{log_info, log_warning};
-
-// ============================================================================
-// Core Path Detection
-// ============================================================================
-
-/// Find the Steam installation path.
-#[must_use]
-pub fn find_steam_path() -> Option<PathBuf> {
-    let home = std::env::var("HOME").ok()?;
-
-    let steam_paths = [
-        format!("{}/.steam/steam", home),
-        format!("{}/.local/share/Steam", home),
-        format!("{}/.var/app/com.valvesoftware.Steam/.steam/steam", home),
-        format!("{}/snap/steam/common/.steam/steam", home),
-    ];
-
-    steam_paths
-        .iter()
-        .map(PathBuf::from)
-        .find(|p| p.exists())
-}
-
-/// Find the Steam userdata directory.
-#[must_use]
-pub fn find_userdata_path() -> Option<PathBuf> {
-    let config = crate::config::AppConfig::load();
-    if !config.selected_steam_account.is_empty() {
-        if let Some(path) = find_userdata_path_for_account(&config.selected_steam_account) {
-            return Some(path);
-        }
-    }
-
-    let steam_path = find_steam_path()?;
-    let userdata = steam_path.join("userdata");
-
-    if !userdata.exists() {
-        return None;
-    }
-
-    let accounts = get_steam_accounts();
-
-    if let Some(most_recent) = accounts.iter().find(|a| a.most_recent) {
-        let path = userdata.join(&most_recent.account_id);
-        if path.exists() {
-            log_info(&format!(
-                "Using Steam account from loginusers.vdf (MostRecent): {} ({})",
-                most_recent.persona_name, most_recent.account_id
-            ));
-            return Some(path);
-        }
-    }
-
-    if let Some(first_account) = accounts.first() {
-        let path = userdata.join(&first_account.account_id);
-        if path.exists() {
-            log_info(&format!(
-                "Using Steam account from loginusers.vdf (most recent timestamp): {} ({})",
-                first_account.persona_name, first_account.account_id
-            ));
-            return Some(path);
-        }
-    }
-
-    log_warning("Could not determine active Steam account from loginusers.vdf, falling back to directory modification time");
-
-    let mut user_dirs: Vec<PathBuf> = Vec::new();
-
-    if let Ok(entries) = fs::read_dir(&userdata) {
-        for entry in entries.flatten() {
-            let path = entry.path();
-            if path.is_dir() {
-                if let Some(name) = path.file_name() {
-                    let name_str = name.to_string_lossy();
-                    if name_str != "0" && name_str.chars().all(|c| c.is_ascii_digit()) {
-                        user_dirs.push(path);
-                    }
-                }
-            }
-        }
-    }
-
-    user_dirs.sort_by(|a, b| {
-        let a_time = fs::metadata(a).and_then(|m| m.modified()).ok();
-        let b_time = fs::metadata(b).and_then(|m| m.modified()).ok();
-        b_time.cmp(&a_time)
-    });
-
-    user_dirs.into_iter().next()
-}
-
-// ============================================================================
-// Steam Account Detection (loginusers.vdf parsing)
-// ============================================================================
-
-/// Information about a Steam user account
-#[derive(Debug, Clone)]
-pub struct SteamAccount {
-    pub account_id: String,
-    pub persona_name: String,
-    pub most_recent: bool,
-    pub timestamp: u64,
-}
-
-/// Get all Steam accounts from loginusers.vdf with their display names
-#[must_use]
-pub fn get_steam_accounts() -> Vec<SteamAccount> {
-    let Some(steam_path) = find_steam_path() else {
-        return Vec::new();
-    };
-
-    let loginusers_path = steam_path.join("config/loginusers.vdf");
-    let userdata_path = steam_path.join("userdata");
-
-    let Ok(content) = fs::read_to_string(&loginusers_path) else {
-        return Vec::new();
-    };
-
-    let mut accounts = Vec::new();
-
-    let mut current_steam_id: Option<String> = None;
-    let mut current_account: Option<SteamAccountBuilder> = None;
-
-    for line in content.lines() {
-        let trimmed = line.trim();
-
-        if trimmed.starts_with('"') && trimmed.ends_with('"') {
-            let id = trimmed.trim_matches('"');
-            if id.len() == 17 && id.starts_with("7656") && id.chars().all(|c| c.is_ascii_digit()) {
-                if let (Some(steam_id), Some(builder)) = (current_steam_id.take(), current_account.take()) {
-                    if let Some(account) = builder.build(&steam_id, &userdata_path) {
-                        accounts.push(account);
-                    }
-                }
-                current_steam_id = Some(id.to_string());
-                current_account = Some(SteamAccountBuilder::default());
-            }
-        }
-
-        if let Some(ref mut builder) = current_account {
-            if let Some((key, value)) = parse_vdf_kv(trimmed) {
-                match key.to_lowercase().as_str() {
-                    "accountname" => builder.account_name = Some(value),
-                    "personaname" => builder.persona_name = Some(value),
-                    "mostrecent" => builder.most_recent = value == "1",
-                    "timestamp" => builder.timestamp = value.parse().unwrap_or(0),
-                    _ => {}
-                }
-            }
-        }
-    }
-
-    if let (Some(steam_id), Some(builder)) = (current_steam_id, current_account) {
-        if let Some(account) = builder.build(&steam_id, &userdata_path) {
-            accounts.push(account);
-        }
-    }
-
-    accounts.sort_by(|a, b| b.timestamp.cmp(&a.timestamp));
-
-    accounts
-}
-
-#[derive(Default)]
-struct SteamAccountBuilder {
-    account_name: Option<String>,
-    persona_name: Option<String>,
-    most_recent: bool,
-    timestamp: u64,
-}
-
-impl SteamAccountBuilder {
-    fn build(self, steam_id: &str, userdata_base: &std::path::Path) -> Option<SteamAccount> {
-        let account_name = self.account_name?;
-        let persona_name = self.persona_name.unwrap_or_else(|| account_name.clone());
-
-        let steam64: u64 = steam_id.parse().ok()?;
-        let account_id = (steam64 - 76561197960265728).to_string();
-
-        let userdata_path = userdata_base.join(&account_id);
-
-        if !userdata_path.exists() {
-            return None;
-        }
-
-        Some(SteamAccount {
-            account_id,
-            persona_name,
-            most_recent: self.most_recent,
-            timestamp: self.timestamp,
-        })
-    }
-}
-
-/// Parse a VDF key-value pair like: "Key"    "Value"
-fn parse_vdf_kv(line: &str) -> Option<(String, String)> {
-    let mut parts = Vec::new();
-    let mut current = String::new();
-    let mut in_quotes = false;
-
-    for c in line.chars() {
-        match c {
-            '"' => {
-                if in_quotes {
-                    parts.push(current.clone());
-                    current.clear();
-                }
-                in_quotes = !in_quotes;
-            }
-            _ if in_quotes => current.push(c),
-            _ => {}
-        }
-    }
-
-    if parts.len() >= 2 {
-        Some((parts[0].clone(), parts[1].clone()))
-    } else {
-        None
-    }
-}
-
-/// Find the userdata path for a specific Steam account
-#[must_use]
-pub fn find_userdata_path_for_account(account_id: &str) -> Option<PathBuf> {
-    let steam_path = find_steam_path()?;
-    let userdata = steam_path.join("userdata").join(account_id);
-
-    if userdata.exists() {
-        Some(userdata)
-    } else {
-        None
-    }
-}
-
-// ============================================================================
-// Convenience Wrappers
-// ============================================================================
-
-/// Detect the Steam installation path with logging.
-#[must_use]
-pub fn detect_steam_path_checked() -> Option<String> {
-    match find_steam_path() {
-        Some(path) => {
-            let path_str = path.to_string_lossy().to_string();
-            log_info(&format!("Steam detected at: {}", path_str));
-            Some(path_str)
-        }
-        None => {
-            log_warning("Steam installation not detected! NaK requires Steam to be installed.");
-            None
-        }
-    }
-}