feat: add Obsidian CLI API service

- Add Docker image for the official Obsidian desktop app and CLI.

- Start Obsidian headlessly with Xvfb and DBus setup.

- Expose a safe structured HTTP command API without shell execution.

- Add JWT-based vault, path, and command authorization.

- Support single-vault and multi-vault container mounts.

- Add TypeScript SDK helpers for Obsidian CLI commands.

- Add n8n community node package with Obsidian operations.

- Add docs, compose config, tests, and production image workflow.

docker-compose.yml

@@ -0,0 +1,30 @@
+services:
+  obsidian-api:
+    build:
+      context: .
+      args:
+        OBSIDIAN_VERSION: ${OBSIDIAN_VERSION:-1.12.7}
+    image: obsidian-api:local
+    container_name: obsidian-api
+    restart: unless-stopped
+    environment:
+      # JWT signing secret. Bearer tokens are HS256 JWTs with vault/path/command claims.
+      OBSIDIAN_JWT_SECRET: ${OBSIDIAN_JWT_SECRET:-}
+      OBSIDIAN_CLI_BIN: ${OBSIDIAN_CLI_BIN:-obsidian}
+      # Single-vault fallback. For multiple vaults, set OBSIDIAN_VAULTS below.
+      OBSIDIAN_VAULT_PATH: /vault
+      # Multi-vault syntax: name=/container/path,name2=/container/path2
+      # Example with the optional /vaults mount below: main=/vault,work=/vaults/work,personal=/vaults/personal
+      OBSIDIAN_VAULTS: ${OBSIDIAN_VAULTS:-}
+      OBSIDIAN_STARTUP_TIMEOUT: ${OBSIDIAN_STARTUP_TIMEOUT:-60}
+      COMMAND_TIMEOUT: ${COMMAND_TIMEOUT:-60}
+      MAX_COMMAND_TIMEOUT: ${MAX_COMMAND_TIMEOUT:-300}
+    volumes:
+      # Default/single vault mount.
+      - ${OBSIDIAN_VAULT_PATH:-./vault}:/vault
+      # Optional parent-folder mount for multiple vaults. Example:
+      # OBSIDIAN_VAULTS_ROOT=/home/daniel/Documents/Obsidian
+      # OBSIDIAN_VAULTS=main=/vault,work=/vaults/Work,personal=/vaults/Personal
+      - ${OBSIDIAN_VAULTS_ROOT:-./vaults}:/vaults
+    ports:
+      - "${OBSIDIAN_API_PORT:-8080}:8080"