fix(ci): remove in-place package build output before the coverage run

[JSONbored]

Problem

Since the 3-shard consolidation (#8514), every packages/** PR fails codecov/patch at (0%/99%) — the last several contributor PRs were auto-closed for it. The consolidation moved the --force miner/MCP builds into the same job as the coverage run. Both packages compile in place (tsconfig outDir: "."), so the builds leave compiled .js siblings next to every .ts under packages/loopover-{miner,mcp}/{lib,bin}. Once those exist, Vite resolves the packages' NodeNext .js-suffixed import specifiers to the real compiled files instead of the .ts fallback vitest.config.ts's coverage globs depend on — breaking the run twice over:

• --changed's import-graph tracing can't relate a changed .ts to the tests that import it (the graph holds the .js identity)
• executed-module coverage is attributed to the .js ids, flatlining every changed .ts to 0%

Reproduced + bisected locally on vitest 4.1.9 against a failing PR's diff shape: with lib/*.js present the scoped run selects 1 test file and reports the changed attempt-cli.ts at 0%; on a clean tree it selects 4 test files and reports 100% / 99.48% branch. The failing CI runs' uploads confirm it — the backend lcov reached Codecov containing only the changed file at 0% (project stayed green via rees/control-plane carryforward, masking the breakage).

Fix

• git clean -fdX packages/loopover-miner packages/loopover-mcp after build verification, before "Test with coverage" (-fdX can only remove gitignored files; the turbo cache save above already captured the outputs)
• check-miner-package.test.ts — the one test that genuinely needs the built artifacts (npm-pack dry-run; both CLI harnesses spawn the .ts entrypoints via --experimental-strip-types) — is now always excluded from the coverage run and re-run at the end of the job after a rebuild, gated exactly like its old in-suite inclusion (push, or minerTestHarness PRs)

Validated locally: YAML parses; the rebuild + standalone vitest run --coverage.enabled=false test/unit/check-miner-package.test.ts passes (17/17).

[superagent-security]

Superagent didn't find any vulnerabilities or security issues in this PR.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 89.58%. Comparing base (12aa3e6) to head (db0f354).
⚠️ Report is 3 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #8564      +/-   ##
==========================================
- Coverage   92.51%   89.58%   -2.93%     
==========================================
  Files         795       97     -698     
  Lines       79613    22706   -56907     
  Branches    24056     3872   -20184     
==========================================
- Hits        73653    20341   -53312     
+ Misses       4800     2187    -2613     
+ Partials     1160      178     -982     

Flag	Coverage Δ
backend	?
control-plane	99.85% <ø> (ø)
rees	88.56% <ø> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.
see 698 files with indirect coverage changes