Fix chat input placeholder text capitalization: Change "Coding Agent" to "coding agent" (#7489)

* Initial plan

* Fix capitalization: Change "Coding Agent" to "coding agent" in chat UI

Co-authored-by: bamurtaugh <25310137+bamurtaugh@users.noreply.github.com>

* Revert unnecessary changes, keep only chat placeholder text fix

Co-authored-by: bamurtaugh <25310137+bamurtaugh@users.noreply.github.com>

---------

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: bamurtaugh <25310137+bamurtaugh@users.noreply.github.com>

Author: Copilot

package.json

@@ -73,7 +73,7 @@
 			{
 				"type": "copilot-swe-agent",
 				"name": "copilot",
-				"displayName": "GitHub Copilot Coding Agent",
+				"displayName": "GitHub Copilot coding agent",
 				"description": "Chat session for GitHub Copilot coding agent",
 				"when": "config.chat.agentSessionsViewLocation && config.chat.agentSessionsViewLocation != 'disabled'"
 			}