Drop legacy registry format from examples, chart, and docs

[rdimitrov]

Summary

• The server only consumes the MCP Registry v0.1 (upstream) format — the legacy ToolHive schema is no longer parsed, but examples, the Helm chart, and the docs were still steering users toward pkg/catalog/toolhive/data/registry-legacy.json and shipping a legacy-format example file.
• Replaces all references with pkg/catalog/toolhive/data/registry-upstream.json (the upstream-format file already living in stacklok/toolhive-catalog), deletes the examples/toolhive-registry.json fixture, and trims sample configs that previously demoed both formats.
• No Go code changes — earlier sweep confirmed no parsers, conversion code, or types specific to the legacy format remained.

Notable example reshuffles

• config-docker-dual.yaml no longer demos two formats; rewritten as two upstream sources with distinct per-source name filters (database-* vs git-*).
• config-docker-multiple.yaml drops the redundant toolhive-file source; still demos file/api/git source kinds.
• examples/README.md data-format section collapsed to describe the single supported format and the API-source description no longer mentions an old "convert from upstream to ToolHive" step.

Test plan

• task gen
• task lint-fix — 0 issues
• go test ./examples/... — all config-*.yaml validate against internal/config
• helm lint deploy/charts/toolhive-registry-server and helm template succeed
• Auto-generated deploy/charts/toolhive-registry-server/README.md regenerated via helm-docs
• Manual smoke test: helm template of the chart produces a ConfigMap with path: pkg/catalog/toolhive/data/registry-upstream.json (and no registry-legacy.json references)
• CI passes

🤖 Generated with Claude Code

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
⚠️ Please upload report for BASE (main@fa6d401). Learn more about missing BASE report.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #774   +/-   ##
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  Coverage        ?   61.05%           
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  Files           ?      108           
  Lines           ?    10593           
  Branches        ?        0           
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  Hits            ?     6468           
  Misses          ?     3547           
  Partials        ?      578           

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[ChrisJBurns]

@claude Has our friend @rdimitrov missed any reference examples of the legacy format from this codebase?

[rdimitrov]

@claude did I missed any reference examples of the legacy format from this codebase?

[claude]

Claude finished @rdimitrov's task in 1m 10s —— View job

---

Legacy format reference audit

• Gather context and understand the request
• Search for remaining registry-legacy.json references
• Search for remaining toolhive-registry.json references
• Search for other legacy format indicators
• Report findings

---

No missed references found. The sweep was exhaustive — searched all .go, .yaml, .yml, .json, .md, .toml, .html, .ts, and .js files for:

• registry-legacy — 0 hits
• toolhive-registry.json — 0 hits
• legacy (case-insensitive) — 3 hits, none related to the registry format:
  • internal/sync/manager_test.go:114 — a comment about stale IN_PROGRESS DB rows ("legacy data"), unrelated to the file format
  • internal/filtering/filter_service_test.go:235,238 — a test fixture named "legacy-api" and a test URL legacy.example.com, both unrelated
• pkg/catalog/toolhive/data/ path — all 20+ occurrences now correctly reference registry-upstream.json

All the changed files in this PR have been properly updated, and the deleted examples/toolhive-registry.json fixture has no surviving references. The PR is clean.

CI is also green ✓