fix: prevent context condensing on settings save when provider/model unchanged

Fixes #4430

The issue was that saving settings during an active task would unconditionally rebuild the API handler in both upsertProviderProfile and activateProviderProfile, even when the provider and model hadn't changed. This caused transient changes to model metadata (contextWindow, maxTokens) which triggered the allowedTokens fast-path in context condensing logic, causing immediate condensing regardless of the configured threshold.

Changes:
- Added guard in upsertProviderProfile to only rebuild API handler when provider OR model changes
- Added guard in activateProviderProfile to only rebuild API handler when provider OR model changes
- Added comprehensive test suite to verify handler is not rebuilt unnecessarily

This prevents the "condense on save" behavior reported in issue #4430 while still rebuilding the handler when genuinely needed (provider or model change).

Author: daniel-lxs

src/core/webview/ClineProvider.ts

@@ -42,6 +42,7 @@ import {
 	ORGANIZATION_ALLOW_ALL,
 	DEFAULT_MODES,
 	DEFAULT_CHECKPOINT_TIMEOUT_SECONDS,
+	getModelId,
 } from "@roo-code/types"
 import { TelemetryService } from "@roo-code/telemetry"
 import { CloudService, BridgeOrchestrator, getRooCodeApiUrl } from "@roo-code/cloud"
@@ -1344,7 +1345,19 @@ export class ClineProvider
 				// TODO: We should rename `buildApiHandler` for clarity (e.g. `getProviderClient`).
 				const task = this.getCurrentTask()
 
-				if (task) {
+				if (task && task.apiConfiguration) {
+					// Only rebuild API handler if provider or model actually changed
+					// to avoid triggering unnecessary context condensing
+					const currentProvider = task.apiConfiguration.apiProvider
+					const newProvider = providerSettings.apiProvider
+					const currentModelId = getModelId(task.apiConfiguration)
+					const newModelId = getModelId(providerSettings)
+
+					if (currentProvider !== newProvider || currentModelId !== newModelId) {
+						task.api = buildApiHandler(providerSettings)
+					}
+				} else if (task) {
+					// Fallback: rebuild if apiConfiguration is not available
 					task.api = buildApiHandler(providerSettings)
 				}
 			} else {
@@ -1405,7 +1418,19 @@ export class ClineProvider
 		// Change the provider for the current task.
 		const task = this.getCurrentTask()
 
-		if (task) {
+		if (task && task.apiConfiguration) {
+			// Only rebuild API handler if provider or model actually changed
+			// to avoid triggering unnecessary context condensing
+			const currentProvider = task.apiConfiguration.apiProvider
+			const newProvider = providerSettings.apiProvider
+			const currentModelId = getModelId(task.apiConfiguration)
+			const newModelId = getModelId(providerSettings)
+
+			if (currentProvider !== newProvider || currentModelId !== newModelId) {
+				task.api = buildApiHandler(providerSettings)
+			}
+		} else if (task) {
+			// Fallback: rebuild if apiConfiguration is not available
 			task.api = buildApiHandler(providerSettings)
 		}