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After merging master, #8309's perf wins target functions that either no
longer exist (wrapExecute / wrapFields / pathToArray / finishResolvers
moved out of instrumentations/graphql.js) or live in a deleted file
(resolve.js was folded into execute.js). Port the still-applicable
changes onto the migrated execute plugin:

  #1 _startResolveSpan uses info.fieldNodes[0] instead of .find(fn =>
     fn.kind === 'Field'). The executor only hands FieldNode siblings.
  #2 pathToArray switches to count-then-fill (drops the trailing
     .reverse() and the push-grow).
  #3 getResolverInfo lazy-allocates resolverVars: skips both the
     up-front {} and the directive-loop assignment when args is empty
     and no directives have arguments.
  #4 shouldInstrument early-returns on config.depth < 0 (no-limit, the
     default-enabled case) before walking the path.
  #5 buildCollapsedPathString builds the collapsed key in one walk;
     drops the intermediate collapsedPath array. iastResolveCh.publish
     now passes raw path / pathString, matching the contract the old
     resolve.js had with the IAST subscriber.
  drive-by  wrapFields iterates Object.values(type._fields) directly.

  #7 (addVariableTags early-return) already auto-merged during the
     master merge.
  #6 (single documentSources.get in wrapExecute) is already the shape
     of bindStart in the migrated plugin.

The reverted depth=0 bindStart short-circuit (156a557 / ca2d041)
sat at a different position — inside bindStart, gated on _depthDisabled
(config.depth === 0). It was rolled back because piling it on top of
the resolveAsync depth-flag fix didn't move plugin-graphql-long-with-
depth-off any further. This port stays inside shouldInstrument, fires
on config.depth < 0 (the *enabled* default), and targets the hot path
on plugin-graphql-long.

Co-Authored-By: Claude Opus 4.7 (1M context) <[email protected]>

After merging master, #8309's perf wins target functions that either no
longer exist (wrapExecute / wrapFields / pathToArray / finishResolvers
moved out of instrumentations/graphql.js) or live in a deleted file
(resolve.js was folded into execute.js). Port the still-applicable
changes onto the migrated execute plugin:

  #1 _startResolveSpan uses info.fieldNodes[0] instead of .find(fn =>
     fn.kind === 'Field'). The executor only hands FieldNode siblings.
  #2 pathToArray switches to count-then-fill (drops the trailing
     .reverse() and the push-grow).
  #3 getResolverInfo lazy-allocates resolverVars: skips both the
     up-front {} and the directive-loop assignment when args is empty
     and no directives have arguments.
  #4 shouldInstrument early-returns on config.depth < 0 (no-limit, the
     default-enabled case) before walking the path.
  #5 buildCollapsedPathString builds the collapsed key in one walk;
     drops the intermediate collapsedPath array. iastResolveCh.publish
     now passes raw path / pathString, matching the contract the old
     resolve.js had with the IAST subscriber.
  drive-by  wrapFields iterates Object.values(type._fields) directly.

  #7 (addVariableTags early-return) already auto-merged during the
     master merge.
  #6 (single documentSources.get in wrapExecute) is already the shape
     of bindStart in the migrated plugin.

The reverted depth=0 bindStart short-circuit (156a557 / ca2d041)
sat at a different position — inside bindStart, gated on _depthDisabled
(config.depth === 0). It was rolled back because piling it on top of
the resolveAsync depth-flag fix didn't move plugin-graphql-long-with-
depth-off any further. This port stays inside shouldInstrument, fires
on config.depth < 0 (the *enabled* default), and targets the hot path
on plugin-graphql-long.

Co-Authored-By: Claude Opus 4.7 (1M context) <[email protected]>

- #3 (regression from round 5): constraintMatchesSlash no longer treats a '/' that
  appears only inside a character class as slash-spanning. `[^/]+` denies slashes, so
  /:id([^/]+)/users (Express 4) normalizes to /{id}/users again instead of null.
- #2: a non-terminal catch-all (a wildcard with a non-empty segment after it, incl. an
  optional {/*rest}/tail) is rejected at compile (→ null) rather than silently dropped.
- #1: a segment containing two independent optional groups (e.g. :a{.:b}{-:c}) is
  rejected (→ null); our single per-segment regex can't replicate path-to-regexp's
  ordered-alternative assignment, so the combined name could be wrong. Single
  intra-segment optionals (:id{.:format}) are unaffected.
- #4: structural-only optional groups — a {...} wrapping only nested group(s) with no
  segment/token of its own (e.g. the outer braces in /a{{/b}}) — are collapsed by
  reparenting represented groups to their nearest represented ancestor, so /a{{/b}}
  resolves to /a/b | /a instead of always /a.

Adds a regression test per finding (verified against live Express 5).

Co-Authored-By: Claude Opus 4.8 (1M context) <[email protected]>