docs: add eject command page

[TaylorKrusen]

What/Why/How?

• Adds doc page for eject command
• Fixes help message for --project-dir
• Moves new product alert into partial
  • There's an upstream PR with a config change that needs to be merged for this to work.

Check yourself

• [ ] Code changed? - Tested with redoc/reference-docs/workflows (internal)
• [ ] All new/updated code is covered with tests
• [ ] New package installed? - Tested in different environments (browser/node)

Security

• [x] Security impact of change has been considered
• [x] Code follows company security practices and guidelines

[changeset-bot[bot]]

⚠️ No Changeset found

Latest commit: 5770e30e0f642f9cd6628a89d419fde4c2b9eb10

Merging this PR will not cause a version bump for any packages. If these changes should not result in a new version, you're good to go. If these changes should result in a version bump, you need to add a changeset.

This PR includes no changesets

When changesets are added to this PR, you'll see the packages that this PR includes changesets for and the associated semver types

Click here to learn what changesets are, and how to add one.

Click here if you're a maintainer who wants to add a changeset to this PR

[github-actions[bot]]

Command	Mean [ms]	Min [ms]	Max [ms]	Relative
redocly lint packages/core/src/benchmark/benches/rebilly.yaml	977.2 ± 28.8	945.5	1047.6	1.00 ± 0.03
redocly-next lint packages/core/src/benchmark/benches/rebilly.yaml	973.4 ± 10.6	956.3	987.8	1.00

[github-actions[bot]]

Coverage report

St.:grey_question:	Category	Percentage	Covered / Total
🟡	Statements	78.52%	4946/6299
🟡	Branches	67.25%	2043/3038
🟡	Functions	72.84%	818/1123
🟡	Lines	78.81%	4665/5919

Test suite run success

800 tests passing in 121 suites.

Report generated by 🧪jest coverage report action from 5770e30e0f642f9cd6628a89d419fde4c2b9eb10

[TaylorKrusen]

Resolved almost everything but have a couple open items to discuss

[lornajane]

Just the changeset and the build failure (you need to run prettier) to check now