feat(arcrun): mira wiki page with tag filter + accumulated WIP

- landing/app/mira/wiki: tag=mira-wiki list now shows all wiki paragraphs
  (depends on KBDB tag filter exposed in matrix/kbdb commit, separate repo)
- landing: app/mira hub + feed split + various WIP from prior sessions
- registry/components: claude_api / kbdb_create_block / kbdb_get / km_writer /
  platform_crypto / auth_oauth2 contracts + main.go (accumulated)
- .component-builds: pkg-lock updates + index.ts adjustments (WIP)
- .agents/specs/arcrun/frontend-redesign: design notes
- docs/test_credentials, docs/user_requirements/arcrun-landing-page: WIP docs
- cypher-executor: auth-dispatcher / wasi-shim adjustments (WIP)

Includes accumulated work from prior sessions plus the wiki UI tag-filter
update that surfaces the AI-generated wiki paragraphs at /mira/wiki.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

registry/components/kbdb_create_block/component.contract.yaml

@@ -0,0 +1,74 @@
+canonical_id: "kbdb_create_block"
+display_name: "KBDB 建立 Block"
+category: "data"
+version: "v1"
+wasi_target: "preview1"
+stability: "floating"
+runtime_compat:
+  - "cf-workers"
+  - "workerd"
+  - "wazero"
+constraints:
+  max_size_kb: 2048
+  max_cold_start_ms: 50
+  no_network_syscall: false
+  no_filesystem_syscall: true
+  io_model: "stdin_stdout_json"
+input_schema:
+  type: object
+  required: [api_key, content]
+  properties:
+    api_key:
+      type: string
+      description: KBDB partner key（pk_live_xxx 或 ak_xxx）
+    content:
+      type: string
+      description: block 內容
+    type:
+      type: string
+      description: block type（note / chat / page 等，預設 block）
+    parent_id:
+      type: string
+      description: 父 block id（留言鏈用）
+    user_id:
+      type: string
+      description: 擁有者 user_id / namespace
+    source:
+      type: string
+      description: 來源標記
+    page_name:
+      type: string
+      description: 所屬 page
+    tags_json:
+      type: string
+      description: tags JSON 字串
+    kbdb_url:
+      type: string
+      description: KBDB API base（預設 https://kbdb.finally.click）
+output_schema:
+  type: object
+  properties:
+    success:
+      type: boolean
+    data:
+      type: object
+      description: KBDB 回傳（含新 block 的 id）
+    error:
+      type: string
+gherkin_tests:
+  - scenario: "缺 content"
+    given: '{"api_key":"pk_live_x"}'
+    then_contains: '{"success":false'
+  - scenario: "建立留言（type=chat + parent_id）"
+    given: '{"api_key":"pk_live_x","content":"hi","type":"chat","parent_id":"abc"}'
+    then_contains: 'success'
+tags: [data, storage, kbdb, create, primitive]
+description: "建立單一 KBDB block（POST /blocks），不切多 chunks。支援 parent_id 給留言鏈用。Mira 留言/AI 回覆使用，本零件為 P0 必備。"
+config_example: |
+  reply:
+    api_key: "{{secret.kbdb_key}}"
+    content: "我的留言"
+    type: "chat"
+    parent_id: "{{previous_node.output.block_id}}"
+    user_id: "inkstone_leo"
+    page_name: "my-post"