feat(lakebridge): generate analyzer JSON by default

[simone-dbx-labs]

Changes

What does this PR do?

databricks labs lakebridge analyze now generates the analyzer JSON file by default, alongside the Excel report. That matches how migration estimator and UI flows consume analyzer output, without requiring --generate-json true.

Users who only want Excel can opt out with --generate-json false.

Relevant implementation details

• generate_json defaults to True in cli.analyze, LakebridgeAnalyzer.run_analyzer, and AnalyzerRunner.run, so programmatic callers get the same behavior as the CLI.
• Bladespector / databricks-bb-analyzer still receive a -j JSON path whenever JSON generation is enabled (unchanged wiring; only the default flipped).
• Docs (docs/lakebridge/docs/assessment/analyzer/index.mdx): describe default-on JSON, how to skip JSON, and updated help-style flag text.
• Tests: CLI tests with real analyzer fixtures assert default .json presence and generate_json=False skips JSON; mock-based LakebridgeAnalyzer tests cover default vs explicit opt-out (including prompt flows).

Caveats/things to watch out for when reviewing:

• Behavior change: interactive or scripted runs that previously omitted --generate-json will now produce an extra .json file next to the report path (same stem, .json extension). Downstream disk usage and CI fixtures that assumed “Excel only” may need to ignore or clean .json, or pass --generate-json false.
• Documentation screenshot (--help block in the Analyzer guide): text was updated; if the team keeps screenshots in sync with CLI output, verify whether that GIF/screenshot needs a refresh (optional follow-up).

Linked issues

Related to databrickslabs/bladerunner#844 (analyzer JSON default; implemented in Lakebridge CLI).

Functionality

• added relevant user documentation
• added new CLI command
• modified existing command: databricks labs lakebridge analyze

Tests

• manually tested
• added unit tests
• added integration tests

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 64.58%. Comparing base (37bb1b5) to head (ee2b9ba).

Additional details and impacted files

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  Files         103      103           
  Lines        9408     9408           
  Branches      992      992           
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  Hits         6076     6076           
  Misses       3156     3156           
  Partials      176      176           

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[github-actions]

✅ 148/148 passed, 5 skipped, 41m44s total

_{Running from acceptance #4339}