sync_components: consume OnlyWith gated defaults from schema bundle

[bdraco]

What does this implement/fix?

Companion to esphome/esphome#16276, which adds a new default_with: {value, components} (and inverse default_without) field to the schema bundle so cv.OnlyWith defaults — previously dropped entirely because the validator's default property gates on CORE.loaded_integrations (always empty at schema-generation time) — survive into schema.esphome.io.

This PR teaches script/sync_components.py to read the new shape: when a field carries default_with, the catalog entry's default_value and depends_on_component are populated from default_with.value and default_with.components[0] respectively. That gives the dashboard the gating context to apply the default conditionally instead of unconditionally.

The motivating case: esp32_ble_tracker.software_coexistence — declared upstream as cv.OnlyWith(K, "wifi", default=True). With this PR + the upstream change, the schema-derived catalog entry ships:

{
  "key": "software_coexistence",
  "default_value": true,
  "depends_on_component": "wifi"
}

so the dashboard's frontend renders the toggle ON when the user has wifi: configured, and hides the field entirely when they don't (matching ESPHome's runtime "no default applies" behaviour). Without this PR (or with a pre-#16276 schema bundle), software_coexistence would continue to surface as a default-less, always-OFF toggle even when wifi is configured.

Backwards compatibility

Pure addition. Schemas predating #16276 (the current schema.esphome.io publish) ship default only — those flow through _extract_default's existing path unchanged, returning (value, None). The new branch only fires when default_with appears in the raw schema entry, which won't happen until the next ESPHome release publishes a bundle generated by the patched script.

This PR is therefore a no-op against the current schema.esphome.io publish and only starts producing different output once #16276 lands and ships in a release. Tests pin the resolver behaviour against synthetic raw inputs so the wiring stays correct in both schema eras.

Carve-outs

• Multi-component OnlyWith: cv.OnlyWith supports a list of components (all must be loaded). depends_on_component is a single-string field; multi-component gates would need a list. No upstream OnlyWith uses a list today (verified against ESPHome's five existing call sites — all single-component); the resolver picks the first and logs a WARNING. Future extension if a real call site needs it.
• cv.OnlyWithout (default_without): inverse-gate semantics — "default applies when this component is NOT loaded". depends_on_component can't model the inverted gate today, so we surface no default for these fields (no regression — same as before #16276 when the schema dropped them entirely). Tracked as a follow-up; only impact is esp32_ble_beacon.tx_power defaulting to "no value" instead of "3dBm when esp32_hosted is absent".

Types of changes

• Bugfix (non-breaking change which fixes an issue) — bugfix
• New feature (non-breaking change which adds functionality) — new-feature
• Enhancement to an existing feature — enhancement
• Breaking change (fix or feature that would cause existing functionality to not work as expected) — breaking-change
• Refactor (no behaviour change) — refactor
• Documentation only — docs
• Maintenance / chore — maintenance
• CI / workflow change — ci
• Dependencies bump — dependencies

Related issue or feature (if applicable):

• companion to [schema] Surface OnlyWith / OnlyWithout default + gate components in schema generator esphome#16276 (gated to land after that PR ships in an ESPHome release)

Frontend coordination

• No frontend change needed
• Companion frontend PR: esphome/device-builder-dashboard-frontend#

The frontend already reads default_value (PR #181 wired the boolean fallback) and depends_on_component (long-standing). The catalog entries this PR produces fit the existing shape; no frontend change required.

Checklist

• The code change is tested and works locally.
• Pre-commit hooks pass (ruff, codespell, yaml/json/python checks).
• Tests have been added or updated under tests/ where applicable.
• components.json has not been hand-edited (the catalog regen happens via script/sync_components.py after the upstream schema ships).
• Architecture-level changes are reflected in docs/ARCHITECTURE.md and/or docs/API.md.

[codspeed-hq]

Merging this PR will not alter performance

✅ 11 untouched benchmarks

---

_{Comparing feature/onlywith-gated-defaults (96cbe28) with main (c1b88a2)}

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 98.64%. Comparing base (71a79c5) to head (3f5934f).

Additional details and impacted files

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  Files          52       52           
  Lines        5911     5911           
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py3.12	98.59% <ø> (ø)
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[Copilot]

Pull request overview

This PR updates the component-catalog sync pipeline to preserve ESPHome schema defaults gated by cv.OnlyWith (new default_with / default_without shape from the schema bundle), so schema.esphome.io-derived catalog entries can carry both a conditional default value and its gating component.

Changes:

• Teach script/sync_components.py to extract defaults from default_with and populate default_value + depends_on_component accordingly (while leaving default_without unsupported for now).
• Add unit + end-to-end conversion tests to pin default extraction behavior across old (default) and new (default_with) schema shapes.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 3 comments.

File	Description
script/sync_components.py	Adds _extract_default() and wires it into _convert_field() to support default_with gated defaults.
tests/test_sync_components_default_extraction.py	New tests covering _extract_default() and _convert_field() behavior for unconditional and gated defaults.

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[bdraco]

Won't actually work till the new ESPHome release, but thats fine