DLC: Test Coverage Analysis

Run the test suite, measure coverage, and create a GitHub issue for failures and coverage gaps.

Before running, read ../dlc/references/ISSUE-TEMPLATE.md now for the issue format, and read ../dlc/references/REPORT-FORMAT.md now for the findings data structure.

Step 1: Detect Test Framework

Scan for test configuration:

Config / Pattern	Framework	Coverage Tool
`vitest.config.` / `vite.config.` (with test)	Vitest	`@vitest/coverage-v8`
`jest.config.*` / `package.json` (with jest)	Jest	Built-in (`--coverage`)
`pytest.ini` / `pyproject.toml` (with pytest) / `conftest.py`	pytest	`pytest-cov`
`Cargo.toml` + `tests/` dir	cargo test	`cargo-tarpaulin` or `cargo-llvm-cov`
`go.mod` + `*_test.go` files	go test	Built-in (`-cover`)
`.rspec` / `Gemfile` (with rspec)	RSpec	`simplecov`