docs: multi-modality rebrand, 2.0 architecture accuracy, and full OpenAPI coverage (#254)

* docs: rebrand from image-only to multi-modality across docs and metadata

SnapOtter expanded from image-only to 157 tools across 5 modalities
(image, video, audio, document/PDF, data). Update all product-level
copy, metadata, and i18n that still framed it as an image-only tool.

- README, package.json, root llms.txt: multi-modality framing, 157 tools
- OpenAPI info + tags, generated /llms.txt tagline (docs.ts)
- VitePress docs site: hero, getting-started, architecture, security,
  deployment, configuration, developer, supported-formats
- i18n: 10 product keys across all 21 locales (hero, app description,
  privacy notes, AI features, progress messages, getting-started)
- web/demo/landing meta + privacy copy, COMMUNITY_GUIDE, .env.example

Stale tool counts (53/50+/52/70+/35) corrected to 157 throughout.
Database/container deployment claims left unchanged (out of scope).

* docs: fix stale post-rebrand test assertions and README language list

- tests/e2e-docs/homepage.spec.ts: assert the current docs homepage (file toolkit, 157 tools, 5 modalities) instead of the old image-only strings
- tests/unit/api/docs-route.test.ts: sync the reproduced llms.txt tagline with docs.ts
- README.md: 21 languages with the correct list (add Swedish and Chinese Traditional, drop Czech which is not supported)

* docs: correct 2.0 architecture references (Postgres 17 + Redis 8, 3-container stack)

The docs and metadata still described the 1.x stack (SQLite, single container, p-queue). Update them to the current 2.0 reality.

- README: replace the broken single-container `docker run` quick-start with the real Docker Compose stack (app + Postgres 17 + Redis 8); fix the "no Redis, no Postgres" feature bullet
- package.json: description no longer claims a single container
- apps/docs: rewrite database.md for Postgres; configuration.md DB_PATH -> DATABASE_URL + REDIS_URL; architecture.md SQLite/p-queue/better-sqlite3 -> Postgres/BullMQ/pg and add media-engine + doc-engine; developer/security/deployment/docker-tags/getting-started/contributing compose examples now include postgres + redis; index.md + api/ai.md AI count 16 -> 19
- SECURITY.md: Drizzle (SQLite) -> (PostgreSQL)
- landing: enterprise/FeatureHighlights single-container wording; TrustSignals/ToolGrid 150+ -> 157 (dynamic); Pricing/FAQ 15 -> 19 AI tools

* docs(api): document all video, audio, document, and data tool endpoints in OpenAPI

The spec covered only image tools; the Scalar UI and the generated /llms.txt and /llms-full.txt inherited that gap. Add the 104 missing tool endpoints so the API docs match the code.

- Video: 29 endpoints (most long/async; auto-subtitles is AI)
- Audio: 17 (transcribe-audio is AI)
- Document/PDF: 36 (ocr-pdf is AI; conversions are long/async)
- Data: 10
- Image: 12 newer tools (background-replace, blur-background AI; histogram/lqip-placeholder/sprite-sheet custom responses; barcode-generate uses a JSON body)

Each schema is derived from the tool's Zod validator and executionHint (fast -> 200, long -> 202+SSE, AI adds 501 FeatureNotInstalledError, multi-file inputs as arrays), referencing the existing shared schemas. Tool path entries: 64 -> 168. Spec parses as valid YAML with no duplicate paths and only known $refs.

apps/docs/guide/developer.md

@@ -1,5 +1,5 @@
 ---
-description: Local development setup, commands, code conventions, and how to add a new image processing tool to SnapOtter.
+description: Local development setup, commands, code conventions, and how to add a new tool to SnapOtter.
 ---
 
 # Developer guide
@@ -10,7 +10,7 @@ How to set up a local development environment and contribute code to SnapOtter.
 
 - [Node.js](https://nodejs.org/) 22+
 - [pnpm](https://pnpm.io/) 9+ (`corepack enable && corepack prepare pnpm@latest --activate`)
-- [Docker](https://www.docker.com/) (for container builds and AI features)
+- [Docker](https://www.docker.com/) (required for local Postgres + Redis, container builds, and AI features)
 - Git
 
 Python 3.10+ is only needed if you are working on the AI/ML sidecar (background removal, upscaling, OCR).
@@ -20,6 +20,7 @@ Python 3.10+ is only needed if you are working on the AI/ML sidecar (background
 ```bash
 git clone https://github.com/snapotter-hq/snapotter.git
 cd snapotter
+docker compose -f docker-compose.dev.yml up -d   # start Postgres + Redis
 pnpm install
 pnpm dev
 ```
@@ -43,6 +44,8 @@ apps/
 packages/
   shared/           Constants, types, i18n strings
   image-engine/     Sharp-based image operations
+  media-engine/     FFmpeg spawn + progress parsing
+  doc-engine/       qpdf, LibreOffice, ghostscript wrappers
   ai/               Python sidecar bridge for ML models
 tests/
   unit/             Vitest unit tests
@@ -76,7 +79,13 @@ pnpm test:coverage      # tests with coverage report
 
 ## Database
 
-SQLite via Drizzle ORM. The database file lives at `./data/snapotter.db` by default.
+PostgreSQL 17 via Drizzle ORM (pg-core). Local dev requires Postgres and Redis running -- start them with:
+
+```bash
+docker compose -f docker-compose.dev.yml up -d
+```
+
+This gives you Postgres on port 5432 and Redis on port 6379. Then generate and apply migrations:
 
 ```bash
 cd apps/api
@@ -84,7 +93,7 @@ npx drizzle-kit generate   # generate a migration from schema changes
 npx drizzle-kit migrate    # apply pending migrations
 ```
 
-Schema is defined in `apps/api/src/db/schema.ts`. Tables: users, sessions, settings, jobs, apiKeys, pipelines, teams, userFiles.
+Schema is defined in `apps/api/src/db/schema.ts`. Tables: users, sessions, settings, jobs, apiKeys, pipelines, teams, userFiles, roles, auditLog.
 
 ## Adding a new tool