fix(generate-rpcn-connector-docs): buildConfigYaml adds label field to component types that don't support it

[mfernest]

Summary

buildConfigYaml.js unconditionally adds label: "" to the generated example YAML for every component type. However, label is only valid for inputs, outputs, and processors. All other component types — metrics, caches, buffers, tracers, rate-limits, and scanners — do not support label, so the generated examples are incorrect.

Root cause

In tools/redpanda-connect/helpers/buildConfigYaml.js, line 27:

module.exports = function buildConfigYaml(type, connectorName, children, includeAdvanced) {
  const lines = [];
  lines.push(`${type}:`);
  lines.push(`  label: ""`);  // ← always added, no type check
  lines.push(`  ${connectorName}:`);
  // ...
}

The caller in generate-rpcn-connector-docs.js (lines 473–492) iterates over all types and calls commonConfig / advancedConfig without filtering, so buildConfigYaml is invoked for all of: buffers, caches, inputs, metrics, outputs, processors, rate-limits, scanners, tracers.

Affected component types (currently incorrect)

Type	# components	Has label?
metrics	7	❌ No
caches	17	❌ No
buffers	4	❌ No
tracers	5	❌ No
rate-limits	2	❌ No
scanners	12	❌ No
inputs	80	✅ Yes
outputs	85	✅ Yes
processors	96	✅ Yes

Suggested fix

In buildConfigYaml.js, guard the label line:

const TYPES_WITH_LABEL = new Set(['inputs', 'outputs', 'processors']);

module.exports = function buildConfigYaml(type, connectorName, children, includeAdvanced) {
  const lines = [];
  lines.push(`${type}:`);
  if (TYPES_WITH_LABEL.has(type)) {
    lines.push(`  label: ""`);
  }
  lines.push(`  ${connectorName}:`);
  // ...
}

Impact

This was reported by a community member via Slack (DOC-1978) specifically for the metrics pages. A manual fix was applied in rp-connect-docs#381 for the metrics examples, but the same bug affects 5 other component type categories and will reappear on the next doc generation run without a fix here.