fix(interactions): remove wf:id from the legal target-value table

[jmartinez-wf]

The problem

SKILL.md's target-value table listed wf:id as a legal target key:

| `wf:id` | element DOM id |

It is refused for every caller, in every context:

target type "wf:id" is not offered by the Designer (shouldShow: false in all
contexts). Use wf:selector, wf:class, or wf:inst instead.

The skill already knows this — references/envelope-and-targets.md carries a [REJECTED] wf:id in any context rule, and references/rejects-index.md lists the refusal fragment. So the skill contradicted itself, and the contradiction sat in the one place an agent is most likely to read: the table you scan to pick a target key.

The failure mode is quiet and total. There's no partial success — an agent that picks wf:id gets a rejection on a write it had no reason to doubt, and the artifact it would cross-check against says the opposite.

What's different now

The row is gone, replaced with an explicit statement of the rejection and the actual alternative (wf:selector with '#the-id'), plus the correct count: seven authorable target keys, not eight.

How this was found

Run 5 of the IX3 MCP exhaustive authoring dogfood, recorded as finding C1 and ranked the highest-priority skill fix. It cost a coverage cell: the run's own handoff also listed "Target types (8)" including wf:id, inherited from this table, so the error had already propagated into planning docs before it hit a write.

Scope note — why this PR is smaller than the finding

The same run found two more issues in this skill, and both live in generated files I deliberately did not touch:

1. references/envelope-and-targets.md has the same wf:id row in its own value-shape table.
2. references/gated-capabilities.md lists wf:variable, wf:rive and wf:animate-rive as flag-gated actions. They were ungated by webflow#120253 (merged 2026-09-09). On monorepo dev all three are now in DEFAULT_ON_ACTION_KEYS and FLAG_GATED_ACTION_KEYS is an empty set — no action type is flag-gated any more. The dogfood run exercised all three successfully, including every wf:variable value type end to end. An agent working from the skill alone would not attempt the three most capable action types on the surface.

Both files open with:

<!-- Published from the Webflow monorepo: packages/systems/ix3/schema/agent-pack/references/...
     Do not edit here. Edit the source and re-publish. -->

SKILL.md has no such header, so it is hand-maintained here and is fixed in this PR.

The agent-pack source is not yet on monorepo dev — it is in open PR webflow#117458. Those two fixes belong in that branch and then a re-publish, so I've left them out rather than editing generated output that the next publish would overwrite.

Validation

• prettier --check on the changed file → clean
• Rejection text quoted verbatim from a measured data_interactions_tool response against beta MCP
• Gating claim verified against monorepo dev source, not just against the run's observations

QA Spec

• SKILL.md's target-value table no longer lists wf:id
• The replacement text names wf:selector with '#the-id' as the way to target by DOM id
• No remaining place in SKILL.md implies wf:id is authorable
• Consistency: SKILL.md now agrees with references/envelope-and-targets.md's [REJECTED] rule and references/rejects-index.md
• Follow-up tracked: the two generated-file corrections land via the agent-pack source, not here