fix(lint): reject non-MemberExpression colinear under resolvedType

[monga-puneet]

Summary

A reasoning action whose colinear value is a bare identifier, string literal, ellipsis, or lone @namespace silently bypassed the resolvedType('invocationTarget') check. The compiler then fell back to target = name, producing a tool that reaches Preview / Agentforce runtime but resolves to no implementation when invoked. Customers saw a clean editor and broken behavior in Preview, with no signal pointing them at the typo.

reasoning:
    actions:
        capture_email: @utils.setVariables   # OK
            with email=...
        hello: world      # silently accepted today; reaches Preview as a no-op tool

This PR extends the constraint validator at packages/language/src/lint/constraint-validation.ts so any non-MemberExpression colinear under a resolvedType constraint emits a constraint-resolved-type Error pointing the author at the expected @namespace.member shape. The fix participates in the existing validatedRefs side channel so undefined-reference does not double-report.

Adds four colocated tests (bare identifier, string literal, ellipsis, lone @utils) to the existing resolvedType constraint describe block.

Test plan

• New unit tests pass; the four pre-existing resolvedType constraint happy-path tests stay green.
• pnpm --filter @agentscript/agentscript-dialect test — 1108/1108.
• pnpm --filter @agentscript/language test — 170/170.
• pnpm --filter @agentscript/agentforce test — 300/300.
• pnpm --filter @agentscript/agentforce-dialect test — 282/282.
• pnpm --filter @agentscript/agentfabric-dialect test — 54/54.
• pnpm --filter @agentscript/compiler test — 801/801.
• Web editor (Monaco) shows red squiggles + Issues panel 2 0 on the bare-identifier repro; hover text reads 'value' must be an @namespace.member invocation target (e.g. @actions.X). Got Identifier.
• Hand-rolled compile harness reports two ERROR[constraint-resolved-type] diagnostics on the repro and zero false positives on @utils.setVariables / @actions.X / @subagent.X / @connected_subagent.X.

[setu4993]

Looks good, see tiny request inline.

[setu4993]

We can afford to be more explicit here about what is supported vs. not. I think @namespace is a bit too abstract.

Suggested change

	`'${fieldName}' must be an @namespace.member ${label} (e.g. @actions.X). Got ${kind}.`,
	`'${fieldName}' must be a member of @utils, @actions, @subagent or @connected_subagent. Got ${kind}.`,

[monga-puneet]

Took the suggestion and went one step further so it stays correct across dialects: enumerate from ctx.invocationTargetNamespaces (drop aliases) plus @utils from globalScopes. agentscript now produces exactly your suggested list; agentforce/agentfabric produce their own correct lists.