Bump KitsuneCommand to v2.6.4 — Modpack feature

[AdaInTheLab]

Summary

Rolls up everything since v2.6.2 into a single release tag. v2.6.3 was bumped on main (#63) but never tagged or released — folding it into v2.6.4 keeps the public release history clean.

What's in v2.6.4

🎯 Modpack (marquee — new in this release)

Bundle installed mods into a single zip players can download from the login page. No panel account required.

• Mods → new Modpack tab with MultiSelect picker, name + version + description
• Three-state lifecycle: draft → published → archived
• Top-right download CTA on the login page when a pack is published
• Anonymous metadata endpoint (`GET /api/modpack/public`) and download endpoint (`GET /api/modpack/public/download`)
• Atomic temp-file zip build so public downloaders can't grab a half-written archive
• Single-source-of-truth: `/KitsuneModpacks/-.zip`

PR: #64

🛠 Server Management improvements

• Graceful Restart (Add GracefulRestart feature: scheduled restarts with in-game warnings #57, Add Server Restart settings tab to admin panel #58) — Scheduled daily restarts with player-friendly in-game countdown warnings. Configurable warning ladder, IANA-timezone schedule (DST-aware), `krestart` console command, REST endpoints, panel Settings tab.

🐛 Bug fixes

• Backups silent write loss (Backups: stop double-opening the SQLite connection (silent write loss) #56) — `BackupService` had a redundant `conn.Open()` call that silently dropped INSERT/UPDATE statements due to a custom System.Data.SQLite quirk. Reads kept working so the bug went unnoticed until first hands-on test. Fix: removed the second `.Open()` at six call sites + class-level doc comment so future-me doesn't reintroduce it.

🌍 Localization

• German, French, Spanish locales (Add German (de) locale + broadcast-not-translated tooltip #59, Add French (fr) locale with polite vous form #61, Add Spanish (es) locale with polite usted form #62) — Full polite-form translations across ~250 keys / 30 namespaces. Browser auto-detect picks the right one for `de-` / `fr-` / `es-*` visitors. Tooltip on the language switcher notes that in-game broadcast messages don't auto-translate.
• 8 supported locales total: English, German, French, Spanish, Chinese Simplified, Chinese Traditional, Japanese, Korean.

✨ Polish

• Favicon (Favicon: regenerate from logo so they match #60) — Regenerated all four variants (svg / 16 / 32 / ico) from `kitsune-command-logo-transparent.png` so the browser tab matches the panel's sidebar logo.
• README — features list updated to reflect everything above.

Files

File	What
`src/KitsuneCommand/ModInfo.xml`	`2.6.3` → `2.6.4`
`README.md`	Modpack feature added to Server Management section

Test plan

• Merge this
• Pull, build, deploy to prod (replaces the current ModInfo=2.6.2 build that's running modpack code)
• Server boot log: `Version value="2.6.4"` in ModInfo, `11 feature(s) initialized`
• Tag `v2.6.4` from the merge commit
• Create GitHub release with notes (this PR's body), attach a `KitsuneCommand-v2.6.4.zip` built from current dist

🤖 Generated with Claude Code