docs: implement Phase 2 - API documentation with TypeDoc

Set up TypeDoc to auto-generate comprehensive API reference documentation
from TypeScript source code.

Changes:
- Installed typedoc and typedoc-plugin-markdown (v0.2.0 plugins)
- Created typedoc.json configuration with 9 entry points
- Added docs:api and docs:watch npm scripts
- Fixed test file imports (validateNamespace → isValidNamespace)
- Updated tsconfig.json to exclude test files from compilation
- Generated markdown API documentation in docs/api-reference/generated/

Generated API documentation:
- 9 modules documented (lib/, hooks/, types/)
- lib/crypto - 14 encryption/certificate functions
- lib/controller - 5 Kubernetes API functions
- lib/validators - 6 validation functions
- lib/retry - Exponential backoff utilities
- lib/rbac - RBAC permission checking
- types - Result types, branded types, interfaces
- hooks/useSealedSecretEncryption - Encryption React hook
- hooks/usePermissions - RBAC React hooks
- hooks/useControllerHealth - Health monitoring hook

Benefits:
- Auto-generated from TypeScript source (stays in sync)
- Markdown format for easy integration
- Type signatures and JSDoc included
- Function parameters and return types documented
- Links between related types and functions

Phase 2 deliverables (2-3 days estimated, completed in 1 session):
✅ TypeDoc installed and configured
✅ Entry points identified for all core modules
✅ API documentation generated (9 modules, 40+ functions)
✅ npm scripts added for docs generation
✅ Test files excluded from documentation

Next: Phase 3 - User tutorials and guides

Generated with [Claude Code](https://claude.ai/code)
via [Happy](https://happy.engineering)

Co-Authored-By: Claude <noreply@anthropic.com>
Co-Authored-By: Happy <yesreply@happy.engineering>

headlamp-sealed-secrets/typedoc.json

@@ -0,0 +1,26 @@
+{
+  "$schema": "https://typedoc.org/schema.json",
+  "entryPoints": [
+    "src/lib/crypto.ts",
+    "src/lib/controller.ts",
+    "src/lib/validators.ts",
+    "src/lib/retry.ts",
+    "src/lib/rbac.ts",
+    "src/types.ts",
+    "src/hooks/useSealedSecretEncryption.ts",
+    "src/hooks/usePermissions.ts",
+    "src/hooks/useControllerHealth.ts"
+  ],
+  "out": "../docs/api-reference/generated",
+  "name": "Headlamp Sealed Secrets API",
+  "exclude": ["**/*.test.ts", "**/*.test.tsx", "**/test-setup.ts"],
+  "excludePrivate": true,
+  "excludeProtected": true,
+  "excludeExternals": true,
+  "plugin": ["typedoc-plugin-markdown"],
+  "readme": "none",
+  "githubPages": false,
+  "disableSources": false,
+  "includeVersion": true,
+  "sort": ["source-order"]
+}