[TypeSpec Validation] Create help page for each rule and link from errors

1. Create folder `eng/tools/typespec-validation/docs/rules`
2. Create a help page for each rule, named the same as the `rule.ts` file (so `compile.md`, `emit-autorest.md`, etc)
* Similar to the help pages for Swagger LintDiff: https://github.com/Azure/azure-openapi-validator/tree/main/docs
4. Add a link to `https://github.com/Azure/azure-rest-api-specs/tree/main/eng/tools/typespec-validation/docs/rules/rule.md` in the error message for each rule.
5. Ideally, show the error message with the link (step 3) directly in the GitHub Checks UI.
* Example showing how to do this from PowerShell in check TypeSpecRequirement (also see file `Logging-Functions.ps1`)
* Related to https://github.com/Azure/azure-rest-api-specs/issues/24999
6. See if docs in `ci-fix.md` should be updated (#25255)