merge: absorb main into next — 23-commit divergence (08-05..13 base=main window)

17 content commits + 3 merge bubbles were genuinely missing from next (~8,000 lines:
goal controller #1152, framework enforcement #1174/#1195, pr-edit wrapper #1173/#1200,
pipefail series #1100/#1105/#1106/#1107, git-tools fixes #1073/#1085/#1086/#1089,
#991, #1007, enrollment tolerance #1094). 3 commits were already in next by content
(#1060 identical, #1066/#1062 evolved twins — conflicts resolved to next's side).

Per-commit classification and evidence: mosaic-brain fleet/lanes/stack-remediation/main-next-divergence.md.
Conflict resolutions (6 files) itemized in the PR body.

packages/mosaic/src/commands/fleet.ts

@@ -486,6 +486,7 @@ function generateAgentEnvValues(
   const workingDirectory = agent.workingDirectory ?? roster.defaults.workingDirectory;
   return {
     MOSAIC_AGENT_NAME: agent.name,
+    MOSAIC_GIT_IDENTITY: agent.name,
     MOSAIC_AGENT_CLASS: agent.className,
     MOSAIC_AGENT_RUNTIME: agent.runtime,
     MOSAIC_AGENT_MODEL: agent.modelHint ?? '',