refactor: wave 1 - extract leaf modules, rename catch-all files, split index.ts hooks

- Split 25+ index.ts files into hook.ts + extracted modules
- Rename all catch-all utils.ts/helpers.ts to domain-specific names
- Split src/tools/lsp/ into ~15 focused modules
- Split src/tools/delegate-task/ into ~18 focused modules
- Separate shared types from implementation
- 155 files changed, 60+ new files created
- All typecheck clean, 61 tests pass

src/tools/lsp/rename-tools.ts

@@ -0,0 +1,53 @@
+import { tool, type ToolDefinition } from "@opencode-ai/plugin/tool"
+
+import { formatApplyResult, formatPrepareRenameResult } from "./lsp-formatters"
+import { withLspClient } from "./lsp-client-wrapper"
+import { applyWorkspaceEdit } from "./workspace-edit"
+import type { PrepareRenameDefaultBehavior, PrepareRenameResult, WorkspaceEdit } from "./types"
+
+export const lsp_prepare_rename: ToolDefinition = tool({
+  description: "Check if rename is valid. Use BEFORE lsp_rename.",
+  args: {
+    filePath: tool.schema.string(),
+    line: tool.schema.number().min(1).describe("1-based"),
+    character: tool.schema.number().min(0).describe("0-based"),
+  },
+  execute: async (args, context) => {
+    try {
+      const result = await withLspClient(args.filePath, async (client) => {
+        return (await client.prepareRename(args.filePath, args.line, args.character)) as
+          | PrepareRenameResult
+          | PrepareRenameDefaultBehavior
+          | null
+      })
+      const output = formatPrepareRenameResult(result)
+      return output
+    } catch (e) {
+      const output = `Error: ${e instanceof Error ? e.message : String(e)}`
+      return output
+    }
+  },
+})
+
+export const lsp_rename: ToolDefinition = tool({
+  description: "Rename symbol across entire workspace. APPLIES changes to all files.",
+  args: {
+    filePath: tool.schema.string(),
+    line: tool.schema.number().min(1).describe("1-based"),
+    character: tool.schema.number().min(0).describe("0-based"),
+    newName: tool.schema.string().describe("New symbol name"),
+  },
+  execute: async (args, context) => {
+    try {
+      const edit = await withLspClient(args.filePath, async (client) => {
+        return (await client.rename(args.filePath, args.line, args.character, args.newName)) as WorkspaceEdit | null
+      })
+      const result = applyWorkspaceEdit(edit)
+      const output = formatApplyResult(result)
+      return output
+    } catch (e) {
+      const output = `Error: ${e instanceof Error ? e.message : String(e)}`
+      return output
+    }
+  },
+})