Add inline docs for aws_ecr_credentials data source

[eon-pulumi-agent]

Problem

The aws_ecr_credentials data source (ecr.getCredentials()) has an empty registry docs page with no attribute descriptions: https://www.pulumi.com/registry/packages/aws/api-docs/ecr/getcredentials/

Fixes #1817.

Root cause

aws_ecr_credentials is not an upstream Terraform data source. It is a Pulumi-side shim over the upstream aws_ecr_authorization_token data source, created in addLegacyECRCredentialsDataSource (provider/resources.go) and retained for v6 backwards compatibility. Because it has no upstream doc file, it was configured with:

"aws_ecr_credentials": {
    Docs: &info.Doc{ AllowMissing: true },
    ...
}

AllowMissing: true suppresses the missing-docs error and leaves the page empty.

Fix

Replace AllowMissing with inline Markdown docs tailored to the shim's actual schema. The shim differs from aws_ecr_authorization_token in that registry_id is required and region is omitted, so the docs are written to match rather than reusing the upstream doc source verbatim.

The markdown uses standard Terraform-website conventions (frontmatter, ## Argument Reference / ## Attribute Reference) and Terraform snake_case field names, which the bridge's docs pipeline matches against schema properties and translates to each target language (the argument-bullet parser only recognizes lowercase/snake_case names, so camelCase would silently fail to attach descriptions).

Testing

• provider package compiles.
• Added TestECRCredentialsHasInlineDocs verifying the data source ships non-empty inline Markdown and no longer relies on AllowMissing; it passes.
• gofmt clean.

Note: a full make schema / SDK regeneration (long-running) was not run in this session; the change is a docs-only override and the markdown structure mirrors the upstream ecr_authorization_token.html.markdown that the pipeline already processes correctly.

Difficulty assessment (per the issue request)

Low. This is a small, well-contained override change in one provider file plus a test — no upstream patch or schema-shape changes required.

---

Created with Eon

[jkodroff]

@corymhall The changes look reasonable to me. I thought this would require SDK generation, tho. Not sure. I can be responsible for any required changes on this PR.

[github-actions]

Does the PR have any schema changes?

Generated by schema-tools v0.8.1.

Looking good! No breaking changes found.
No new resources/functions/types.

Maintainer note: consult the runbook for dealing with any breaking changes.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 15.85%. Comparing base (30ddf87) to head (004e711).

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #6615   +/-   ##
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  Coverage   15.85%   15.85%           
=======================================
  Files         376      376           
  Lines       92842    92842           
=======================================
  Hits        14724    14724           
  Misses      78096    78096           
  Partials       22       22           

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[corymhall]

The changes look reasonable to me. I thought this would require SDK generation, tho. Not sure. I can be responsible for any required changes on this PR.

@jkodroff I think it might require SDK generation as well. It looks like Eon thought it didn't need to run anything.