feat(coding-agent): added automatic deduplication of context files by content

- Added automatic deduplication of identical context files by content, keeping the closest (lowest depth) copy when duplicates are discovered.
- Implemented dedupeExactContextFiles() function to filter duplicate context entries in both explicit and discovered file lists.
- Added 3 test cases covering deduplication of explicit context entries, discovered context entries, and preservation of distinct entries.

packages/coding-agent/src/modes/controllers/selector-controller.ts

@@ -639,6 +639,14 @@ export class SelectorController {
 		this.ctx.pendingTools.clear();
 	}
 
+	#refreshSessionTerminalTitle(): void {
+		const sessionManager = this.ctx.sessionManager as {
+			getSessionName?: () => string | undefined;
+			getCwd: () => string;
+		};
+		setSessionTerminalTitle(sessionManager.getSessionName?.(), sessionManager.getCwd());
+	}
+
 	async #detachActiveSessionBeforeDeletion(sessionPath: string): Promise<boolean> {
 		const currentSessionFile = this.ctx.sessionManager.getSessionFile();
 		if (currentSessionFile !== sessionPath) {
@@ -649,7 +657,7 @@ export class SelectorController {
 		if (!detached) {
 			return false;
 		}
-		setSessionTerminalTitle(this.ctx.sessionManager.getSessionName(), this.ctx.sessionManager.getCwd());
+		this.#refreshSessionTerminalTitle();
 
 		this.#clearTransientSessionUi();
 		this.ctx.statusLine.invalidate();
@@ -666,7 +674,7 @@ export class SelectorController {
 
 		// Switch session via AgentSession (emits hook and tool session events)
 		await this.ctx.session.switchSession(sessionPath);
-		setSessionTerminalTitle(this.ctx.sessionManager.getSessionName(), this.ctx.sessionManager.getCwd());
+		this.#refreshSessionTerminalTitle();
 
 		// Clear and re-render the chat
 		this.ctx.chatContainer.clear();