refactor(fase0): shared scaffold — crypto, file-url, schemas, test splits

- Add zod dep; new src/shared/validation/schemas.ts (BucketName,
  JsonUploadPayload, LoginBody, DeleteObjects, CompleteMultipart,
  clampMaxKeys, parseOrNull) + test/validation.test.ts
- Dedup timingSafeCompare -> src/shared/utils/crypto.ts (auth
  middleware, authenticate use-case, s3/auth now import it)
- Dedup AuthSession -> single type in dto/auth.ts
- Dedup telegram file URL builder + filename sanitizer to shared
  modules (file-controller now imports the canonical ones)
- Remove duplicate controllers/home.html (canonical: src/home.html)
- Fix stale bootstrap mocks to real module paths; bootstrap now
  asserts public GET vs guarded POST separately
- Fix health assertion to include version field
- package.json: test -> test:unit alias; new test:quarantine for
  network/live tests; register previously unlisted test files

bun.lock

@@ -13,6 +13,7 @@
         "postgres": "^3.4.9",
         "telegraf": "^4.15.0",
         "winston": "^3.11.0",
+        "zod": "^4.6.5",
       },
       "devDependencies": {
         "@aws-sdk/client-s3": "^3.1079.0",
@@ -357,6 +358,8 @@
 
     "xtend": ["xtend@4.0.2", "", {}, "sha512-LKYU1iAXJXUgAXn9URjiu+MWhyUXHsvfp7mcuYm9dSUKK0/CjtrUwFAxD82/mCWbtLsGjFIad0wIsod4zrTAEQ=="],
 
+    "zod": ["zod@4.6.5", "", {}, "sha512-v5l/aFXZQeai4awLbOpSoHecE9UiMrnfx75tEXLjNonXVARxQ5mOeipTjROUchszUNCqnE+hqAMujRsRHsut2Q=="],
+
     "@esbuild-kit/core-utils/esbuild": ["esbuild@0.18.20", "", { "optionalDependencies": { "@esbuild/android-arm": "0.18.20", "@esbuild/android-arm64": "0.18.20", "@esbuild/android-x64": "0.18.20", "@esbuild/darwin-arm64": "0.18.20", "@esbuild/darwin-x64": "0.18.20", "@esbuild/freebsd-arm64": "0.18.20", "@esbuild/freebsd-x64": "0.18.20", "@esbuild/linux-arm": "0.18.20", "@esbuild/linux-arm64": "0.18.20", "@esbuild/linux-ia32": "0.18.20", "@esbuild/linux-loong64": "0.18.20", "@esbuild/linux-mipsLine truncated
 
     "bun-types/@types/node": ["@types/node@25.8.0", "", { "dependencies": { "undici-types": ">=7.24.0 <7.24.7" } }, "sha512-TCFSk8IZh+iLX1xtksoBVtdmgL+1IX0fC9BeU4QqFSuNdN/K+HUlhqOzEmSYYpZUVsLYcPqc9KX+60iDuninSQ=="],