fix(admin): resolve all 266 TypeScript errors, enable strict build

Eliminate the pre-existing TS errors that were masked by
next.config.js `typescript.ignoreBuildErrors: true`, then turn the flag
OFF so the compiler is a real safety net for future changes. `next build`
and `tsc --noEmit` now pass with 0 errors.

The errors were not cosmetic — several exposed real latent bugs hidden by
the flag, e.g. the drafting-engine ConstraintEnforcer read non-existent
fields (`t.rule.dsfaRequired`, `d.required`, `r.title`), so its DSFA hard
gate and risk-flag checks were silently no-ops; scopeDefaults read
snake_case CompanyProfile fields that never matched the camelCase type
(generator defaults never populated). Both fixed by aligning code to the
current types.

Highlights:
- Vitest globals: add vitest-globals.d.ts (config already had globals:true)
  so the test files type-check; exclude Playwright specs from vitest.
- Add a minimal ambient `pg` module declaration (no @types/pg installed).
- Fix Next 15 route handlers to await Promise params.
- Reconcile drifted types across loeschfristen, compliance-scope, document-
  generator, drafting-engine, vendor-compliance, agent and more.

Pre-existing (NOT caused here, proven by stashing the diff): 3 vitest
logic tests still fail — getNextStep (2) and buildDocumentScope priority (1).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

admin-compliance/app/sdk/sdk-flow/types.ts

@@ -9,7 +9,7 @@ export interface SDKFlowStep {
   package: 'vorbereitung' | 'analyse' | 'dokumentation' | 'rechtliche-texte' | 'betrieb'
   seq: number
   checkpointId?: string
-  checkpointType?: 'REQUIRED' | 'RECOMMENDED'
+  checkpointType?: 'REQUIRED' | 'RECOMMENDED' | 'OPTIONAL' | 'CONDITIONAL'
   checkpointReviewer?: 'NONE' | 'DSB' | 'LEGAL'
 
   // Beschreibung