Add References tab + resolve mutators in Desired State

[edvgui]

Claude opening this PR on behalf of @edvgui.

Summary

Surfaces the references and mutators carried on a resource's desired state in the resource details page.

New "References" tab

Lists every entry in details.attributes.references as an expandable row showing the reference's type and id. Expanding a row reveals its arguments in a Desired-State-lookalike
layout:

• Linked args (type: "reference" / "resource") render as blue clickable chips. Clicking a reference chip expands and scrolls to the target row in the same table.
• mjson args are rendered as a JSON block. Nested references listed under arg.references (JSONPath → reference id) are substituted in place and rendered as inline clickable chips
  inside the JSON text.
• literal args go through the existing AttributeClassifier + AttributeList pipeline so JSON / XML / multi-line formatting matches the Desired State tab exactly.

Expansion state is URL-backed (useUrlStateWithExpansion) so it survives reloads and cross-tab navigation.

Mutator resolution on the Desired State tab

core::Replace mutators are interpreted client-side (see inmanta_core.references.ReplaceValue):

1. Extract (destination, referenceId) pairs from attributes.mutators.
2. Substitute the value at each destination (JSONPath) in a clone of the attributes with a printable sentinel string.
3. Render mutated attribute rows specially — pure-sentinel values become a single chip, mixed-string values become inline chips, complex values become a JSON code block with inline chips.

mutators and references keys are hidden from the Desired State tab (they have dedicated rendering / the References tab).

Cross-tab navigation

Clicking a chip in the Desired State tab switches to the References tab and auto-expands the target row. A small useEffect-based dance defers the expansion to a follow-up render so the
two URL writes (active tab + expansion) don't clobber each other — each useUrlState write captures location.search at render time and would otherwise overwrite the sibling key.

Structured / JSON toggle

A toggle above the Desired State card lets the user flip between the structured view (with mutator chips) and a read-only CodeEditor showing details.attributes verbatim — useful as an
escape hatch when something looks off.

Implementation notes

• Sentinel trick. Inline chips in serialized JSON cannot ride a Monaco-backed CodeEditor. Instead we substitute reference holes with printable sentinels
  (@@INMANTA_REF_START@@<uuid>@@INMANTA_REF_END@@), JSON.stringify, then split the resulting text on the sentinel regex and interleave <Label> chips between text chunks. Earlier draft
  used a real null byte — JSON.stringify escapes it to a 6-char \u0000 sequence, which broke the regex; printable ASCII sidesteps that.
• JSONPath subset. In-house parser handles $ root, [<n>], [<"key">], .key, and bare-name paths (value, foo.bar). No wildcards / filters / recursive descent — sufficient for
  what the orchestrator currently emits via jsonpath_ng. If/when we see richer expressions, swap to jsonpath-plus.
• Mutator support. Only core::Replace is interpreted. Other mutator types are ignored (the original attribute value is rendered as-is) until a use case appears.

Preview

Screencast.From.2026-05-21.23-23-53.mp4

Test plan

• Open a resource with attributes.references populated; References tab appears between Desired State and Requires.
• Expand a reference row — args render with type · id chips for linked args; literal args use the standard formatting.
• Expand a mjson-bearing reference — clickable chips appear inline in the JSON block at each references JSONPath.
• Click a chip — target row expands and scrolls into view.
• Open a resource with core::Replace mutators (see resource.json) — mutated attribute renders as a chip in the Desired State tab; clicking it switches to References tab with the
  target row expanded.
• Toggle Desired State → JSON — full details.attributes is shown in a read-only editor, including mutators and references arrays.
• Resource with no references shows the empty state on the References tab.

🤖 Generated with Claude Code