Add test coverage assessment prompt

[brunoborges]

Adds a new prompt template for test coverage assessment in .github/prompts/test-coverage-assessment.prompt.md.

[Copilot]

Pull request overview

Adds a new GitHub prompt template intended to guide a structured assessment of unit/E2E test coverage for the Java SDK (events, hooks, and core session behaviors).

Changes:

• Introduces a new prompt document for enumerating testable components (events/hooks) and mapping them to existing tests.
• Defines a standardized report format (tables, summary, gaps, and recommendations) and includes verification commands.

Comments suppressed due to low confidence (2)

.github/prompts/test-coverage-assessment.prompt.md:73

• The Hook Types Coverage table example also uses || at the start of each row, which adds an unintended empty column and can prevent proper Markdown table rendering. Switch to single | row delimiters.

| Hook Type | Handler Interface | Unit Test | E2E Test | Notes |
|-----------|-------------------|:---------:|:--------:|-------|
| `preToolUse` | `PreToolUseHandler` | ✅/❌ | ✅/❌ | Any notes |
| ... | ... | ... | ... | ... |

.github/prompts/test-coverage-assessment.prompt.md:80

• The Coverage Summary table example uses || row prefixes, which typically renders as an extra empty first column and misaligned separators. Use standard Markdown table syntax with single leading | per row.

| Category | Total | Unit Tested | E2E Tested | Coverage % |
|----------|-------|-------------|------------|------------|
| Events | X | X | X | X% |
| Hooks | X | X | X | X% |

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

[Copilot]

These Markdown table examples start each row with ||, which creates an extra empty first column and breaks the header separator alignment in most renderers. Use a single leading | for each row so the tables render correctly.

This issue also appears in the following locations of the same file:

• line 70
• line 77