Task: Promote Learning download size removal to main

Identity

Promote the already verified integration tip d16cace into local main.
Keep the reconciled Learning download implementation and canonical project documentation unchanged.
Preserve the unrelated pre-existing untracked task record in the canonical worktree without modifying or committing it.

Remove every client-side archive-size check while retaining authentication, fixed routes, same-origin redirects, SHA-256, ZIP signature validation, temporary-file cleanup, and atomic rename.
Treat the Works Square upload/storage limit as independent from Makelore's download behavior.
Merge only to local main; do not push a remote branch.
Do not create sub-agents, per the user's explicit instruction.

Merged integration tip d16cace into local main through merge commit 399b280.
Removed the completed upstream integration task record from the promoted tree so the canonical worklog contains only the current promotion record.
Preserved .project-docs/30-worklog/tasks/20260819-package-learning-off-115-9c4d.md untouched and untracked.

Upstream integration verification: focused Learning tests 17 passed; full unit suite 176 files / 2061 tests; typecheck passed; lint passed with zero errors and six pre-existing warnings; Renderer/Main/Preload/utility build passed with existing advisory warnings only.
Local main focused Learning tests: 2 files / 17 passed.
Local main pnpm run typecheck: passed.
Removed-size-symbol scan and git diff --check: passed.
Required project-docs structure check: passed.
Task-aware documentation drift check: blocked only by the pre-existing, explicitly preserved untracked record .project-docs/30-worklog/tasks/20260819-package-learning-off-115-9c4d.md; the merged upstream task record was removed from the final tree.

Package and smoke with a real archive response that omits or misreports Content-Length.
Monitor disk-space behavior for very large archives because the client has no archive-size ceiling by explicit product decision.
Decide separately whether to integrate or remove the preserved untracked task record so the task-aware documentation gate can pass and ownership can be released cleanly.