feat(navigation): add symbol index and LSP navigation features

The changes introduce a Tcl symbol index powering LSP navigation
features across the workspace. A navigation API exposes
snapshots and update hooks, enabling goto-definition,
references, and rename using the index. Background indexing
now watches Tcl files and rebuilds the index to stay in sync.

- Add Tcl symbol index and navigation snapshot API
- Wire go-to-definition, references, and rename using the index
- Watch Tcl files and refresh the index in the background

client/src/common/server.ts

@@ -2,7 +2,7 @@
 // Licensed under the MIT License.
 
 import * as fsapi from "fs-extra"
-import { Disposable, env, LogOutputChannel } from "vscode"
+import { Disposable, env, LogOutputChannel, workspace } from "vscode"
 import { State } from "vscode-languageclient"
 import {
     LanguageClient,
@@ -24,6 +24,13 @@ import { isVirtualWorkspace } from "./vscodeapi"
 
 export type IInitOptions = { settings: ISettings[]; globalSettings: ISettings }
 
+let _disposables: Disposable[] = []
+
+export function disposeServerResources(): void {
+    _disposables.forEach((disposable) => disposable.dispose())
+    _disposables = []
+}
+
 async function createServer(
     settings: ISettings,
     serverId: string,
@@ -63,6 +70,7 @@ async function createServer(
     }
 
     // Options to control the language client
+    const tclFileWatcher = workspace.createFileSystemWatcher("**/*.tcl")
     const clientOptions: LanguageClientOptions = {
         // Register the server for python documents
         documentSelector: isVirtualWorkspace()
@@ -76,13 +84,16 @@ async function createServer(
         outputChannel: outputChannel,
         traceOutputChannel: outputChannel,
         revealOutputChannelOn: RevealOutputChannelOn.Never,
+        synchronize: {
+            fileEvents: tclFileWatcher
+        },
         initializationOptions
     }
 
+    _disposables.push(tclFileWatcher)
     return new LanguageClient(serverId, serverName, serverOptions, clientOptions)
 }
 
-let _disposables: Disposable[] = []
 export async function restartServer(
     serverId: string,
     serverName: string,
@@ -92,8 +103,7 @@ export async function restartServer(
     if (lsClient) {
         traceInfo(`Server: Stop requested`)
         await lsClient.stop()
-        _disposables.forEach((d) => d.dispose())
-        _disposables = []
+        disposeServerResources()
     }
     const projectRoot = await getProjectRoot()
     const workspaceSetting = await getWorkspaceSettings(serverId, projectRoot, true)
@@ -122,6 +132,7 @@ export async function restartServer(
         await newLSClient.start()
     } catch (ex) {
         traceError(`Server: Start failed: ${ex}`)
+        disposeServerResources()
         return undefined
     }