refactor: codebase audit cleanup — dead code, dedup, module splits

Multi-agent audit + aggressive cleanup across server/web/coder/booterm,
delivered behind a DEFER discipline so none of the in-flight files were
touched. Removes dead code/deps/columns, dedups server + coder helpers,
and splits the oversized modules (tools.ts, opencode-server.ts,
sentinel-summaries, turn.ts, TerminalPane.tsx) behind stable contracts.
Adds 78 parity/unit tests (server 587, coder 323); fixes two latent bugs
(ChatPane queue keys, FileViewerOverlay blank-line parity).

Intended tag: v2.7.12-audit-cleanup.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

apps/server/src/services/tools/codecontext/get_blast_radius.ts

@@ -1,6 +1,5 @@
 import { z } from 'zod';
-import type { ToolDef } from '../../tools.js';
-import { callCodecontext, type CodecontextResponse } from '../../codecontext_client.js';
+import { makeCodecontextTool } from './factory.js';
 
 export const GetBlastRadiusInput = z.object({
   file_path: z.string().trim().min(1),
@@ -12,40 +11,23 @@ const DESCRIPTION =
   'Use to assess the impact of changing a file — "what breaks if I modify this?" ' +
   'Traverses the import graph in reverse via BFS. Results sorted by distance (closest dependents first).';
 
-export async function executeGetBlastRadius(
-  input: GetBlastRadiusInputT,
-  projectPath: string,
-  fetcher: typeof fetch = fetch,
-): Promise<CodecontextResponse> {
-  return callCodecontext(
-    { toolName: 'get_blast_radius', args: { file_path: input.file_path }, projectPath },
-    fetcher,
-  );
-}
-
-export const getBlastRadius: ToolDef<GetBlastRadiusInputT> = {
-  name: 'get_blast_radius',
-  description: DESCRIPTION,
-  inputSchema: GetBlastRadiusInput,
-  jsonSchema: {
-    type: 'function',
-    function: {
-      name: 'get_blast_radius',
-      description: DESCRIPTION,
-      parameters: {
-        type: 'object',
-        properties: {
-          file_path: {
-            type: 'string',
-            description: 'Absolute or project-relative path to the file to analyze.',
-          },
+const { toolDef: getBlastRadius, execute: executeGetBlastRadius } =
+  makeCodecontextTool<GetBlastRadiusInputT>({
+    name: 'get_blast_radius',
+    schema: GetBlastRadiusInput,
+    description: DESCRIPTION,
+    jsonParameters: {
+      type: 'object',
+      properties: {
+        file_path: {
+          type: 'string',
+          description: 'Absolute or project-relative path to the file to analyze.',
         },
-        required: ['file_path'],
-        additionalProperties: false,
       },
+      required: ['file_path'],
+      additionalProperties: false,
     },
-  },
-  async execute(input, projectRoot) {
-    return await executeGetBlastRadius(input, projectRoot);
-  },
-};
+    mapArgs: (input) => ({ file_path: input.file_path }),
+  });
+
+export { getBlastRadius, executeGetBlastRadius };