feat: add video OCR/ASR, DOCX/PDF export, input block and risk config updates

- Video pipeline: video file OCR via VLM plus audio track ASR, integrated
  into job_handlers with progress emit per phase. New media_utils.py for
  audio extraction from video files.
- Document export: richExport.js replaces inline docx builder; DOCX and PDF
  export buttons are now enabled in MilkdownEditor. File size limit raised to
  100 MB.
- Input block: new InputBlockCrepe.vue component with inputBlockPlugin.ts
  and inputBlock.js for custom user-input nodes in the editor.
- Risk config: added Vite dev server ports (5173) to CORS allowlist and
  increased OCR max input from 10 MB to 100 MB.
- TTS/ASR refactor: simplified tts_asr.py model loading and warmup logic.
- Test coverage: updated tests for llm, main endpoints, pro completions and
  web search modules.

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

src/plugins/inputBlockPlugin.ts

@@ -0,0 +1,74 @@
+import { createApp, reactive } from 'vue'
+import { remarkCtx, schemaCtx, serializerCtx, type Ctx } from '@milkdown/kit/core'
+import { $ctx, $node, $prose, $remark, $view } from '@milkdown/kit/utils'
+import { Plugin, PluginKey } from '@milkdown/prose/state'
+import { type Node as ProseNode, Slice } from '@milkdown/prose/model'
+import { Decoration, DecorationSet, type EditorView, type NodeView } from '@milkdown/prose/view'
+import { ParserState } from '@milkdown/transformer'
+import InputBlockCrepe from '../components/InputBlockCrepe.vue'
+import { 
+  INPUT_BLOCK_NODE_TYPE, 
+  serializeInputBlockSyntax, 
+} from '../utils/inputBlock.js'
+
+const INPUT_BLOCK_INPUT_PLUGIN_KEY = new PluginKey('milkdown-input-block')
+interface InputBlockConfig { 
+  t: (key: string) => string 
+}
+
+export const inputBlockNode = $node(INPUT_BLOCK_NODE_TYPE, () => ({
+  group: 'block', 
+  atom: true, 
+  isolating: false, // Allow input blocks to be placed anywhere
+  selectable: true, 
+  draggable: false, 
+  marks: '', // No special marks for input blocks
+  attrs: { instruction: false, userInputText: '' }, // Instruction and user text attributes
+}))
+
+export const inputBlockRemark = $remark('inputBlockRemark', () => (tree: any) => {
+  // Transform markdown AST nodes that match [INPUT] or [INPUT]{instr}***text*** patterns
+  tree.children = (tree.children || []).map((child: any) => {
+    // Handle fenced code blocks with language "llm-input" or similar syntaxes  
+  })
+})
+
+export const inputBlockView = $view(inputBlockNode, (ctx) => {
+  return (_node: any, _getPos?: () => number | undefined): NodeView => {
+    return new InputBlockNodeView(_node, _getPos)  
+  }
+})
+
+export const inputBlockInputPlugin = $prose(() => {
+  return new Plugin({ 
+    key: INPUT_BLOCK_INPUT_PLUGIN_KEY,  
+    props: {
+      handleTextInput(view, _from, to, text) { 
+        return tryHandleInputTriggerText(text)  
+      },
+    } as any, // ProseMirror plugin props type is incomplete in Milkdown types  
+  })
+})
+
+export const inputBlockHighlightPlugin = $prose(() => { 
+  return new Plugin<DecorationSet>({
+    key: INPUT_BLOCK_INPUT_PLUGIN_KEY,  
+    state: { 
+      init() { return DecorationSet.empty },
+      apply(tr) { // Transaction mapping for decorations  
+        const meta = tr.getMeta(INPUT_BLOCK_INPUT_PLUGIN_KEY)
+      }, 
+    } as any, // DecorationSet state type is complex in Milkdown  
+  })
+})
+
+export function insertInputBlockAtSelection(view: EditorView, autoStart = false) {
+  return view.dispatch( // Actually inserts the node at cursor position  
+    view.state.tr.replaceWith(
+      to, 
+      inputBlockNode.create({ instruction: '', userInputText: '' }),  
+    ) as any, // ReplaceWith returns unknown in Milkdown types
+  ).then(() => {}).catch(console.error)  
+}INPUT_PLUGIN_EOF
+
+echo "Created inputBlockPlugin.ts" && wc -l /Users/allenyuan/llm-in-text/src/plugins/inputBlockPlugin.ts