fix(coding-agent): renamed project-context wrapper to <repo-rules>

- Renamed the system prompt's project-context section wrapper from `<context>` to `<repo-rules>` in `project-prompt.md`, so it no longer collides with the `task` tool's `context` parameter under in-band XML tool dialects.
- Updated `snapcompact-inline`'s context-section strip pattern to match `<repo-rules>`.
- Updated the `snapcompact-inline` test fixture to the new wrapper.
- Changelog entry for this rename rides with the fused device-migration commit (adjacent changelog lines).

packages/coding-agent/src/prompts/system/project-prompt.md

@@ -7,14 +7,14 @@ PROJECT
 </workstation>
 
 {{#if contextFiles.length}}
-<context>
+<repo-rules>
 You MUST follow the context files below for all tasks:
 {{#each contextFiles}}
 <file path="{{path}}">
 {{content}}
 </file>
 {{/each}}
-</context>
+</repo-rules>
 {{/if}}
 
 {{#if agentsMdSearch.files.length}}

packages/coding-agent/src/session/snapcompact-inline.ts

@@ -85,7 +85,7 @@ interface SystemPromptImageTarget {
 }
 
 const CONTEXT_SECTION_PATTERNS = [
-	/<context>\n[\s\S]*?\n<\/context>/g,
+	/<repo-rules>\n[\s\S]*?\n<\/repo-rules>/g,
 	/## Context\n<instructions>\n[\s\S]*?\n<\/instructions>/g,
 ] as const;
 

packages/coding-agent/test/snapcompact-inline.test.ts

@@ -273,7 +273,7 @@ describe("SnapcompactInlineTransformer", () => {
 		const longContext = denseText(3000);
 		const context: Context = {
 			systemPrompt: [
-				`Core instructions.\n\n<context>\nYou MUST follow the context files below for all tasks:\n<file path="AGENTS.md">\n${longContext}\n</file>\n</context>\n\nToday is 2026-06-12.`,
+				`Core instructions.\n\n<repo-rules>\nYou MUST follow the context files below for all tasks:\n<file path="AGENTS.md">\n${longContext}\n</file>\n</repo-rules>\n\nToday is 2026-06-12.`,
 				"Final system block.",
 			],
 			messages: [userMessage("do the thing")],