Fix ScriptComponent clone dropping scripts awaiting their script type

[mvaligursky]

Description

ScriptComponentSystem#cloneComponent iterated _scriptsIndex with for...in and checked key.awaiting, where key is the script name string — so the check was always undefined and the whole block was dead code:

for (const key in entity.script._scriptsIndex) {
    if (key.awaiting) {              // always falsy
        order.splice(key.ind, 0, key);
    }
}

Cloning an entity therefore silently dropped any script whose script type was not in the registry yet. When the type was later registered, the deferred sweep in ScriptRegistry#add created the script on the original entity, but the clone had no awaiting entry so it never got one:

source: _scriptsIndex = [scriptA, loadedLater(awaiting,ind=1), scriptB]
clone : _scriptsIndex = [scriptA, scriptB]
--> after loadedLater is registered
source.script.loadedLater: EXISTS
clone.script.loadedLater : MISSING

Fix

Dereferencing the index entry is not enough on its own:

• The awaiting script also needs an entry in scripts. initializeComponentData looks every name from order up in scripts (data.scripts[data.order[i]].enabled), so a name in order but missing from scripts throws TypeError: Cannot read properties of undefined (reading 'enabled') — a hard throw out of entity.clone() in place of the silent drop. The data comes from _scriptsData, which is also where the registry sweep reads the attributes from when it eventually creates the script.

• The awaiting script needs a well-defined slot. It is placed directly after the script it was declared after, which is where the deferred creation puts it on the source entity (see Create scripts added to the registry later at their declared index #9202), so source and clone converge on the same order.

That needs the declaration order of all scripts, created or not. Neither existing record is that: _scripts only holds created scripts and is reordered by move(), and the key order of _scriptsIndex is not declaration order for every accepted script name (integer-like keys are enumerated first, so ['scriptA', '10', '2', 'scriptB'] enumerates as 2, 10, scriptA, scriptB). So it is recorded explicitly as _declarationOrder, maintained in create() / destroy().

Supersedes #8264, which is the one-line dereference and hits the TypeError above.

Fixes #2796

Testing

Five tests in test/framework/components/script/component.test.mjs, all five fail on main:

• the clone keeps the awaiting entry, its ind, and its declared enabled / attribute data
• consecutive awaiting scripts keep their relative order
• ...including with integer-like script names
• an awaiting script is placed after the script it was declared after, when that has been moved
• the clone gets the instance, in the right slot, once the script type is registered

Checklist

• I have read the contributing guidelines
• My code follows the project's coding standards
• This PR focuses on a single change

🤖 Generated with Claude Code

[github-actions]

Build size report

This PR changes the size of the minified bundles.

Bundle	Minified	Gzip	Brotli
playcanvas.min.js	2371.8 KB (+0.4 KB, +0.02%)	609.5 KB (+0.1 KB, +0.02%)	473.4 KB (+0.1 KB, +0.01%)
playcanvas.min.mjs	2369.2 KB (+0.4 KB, +0.02%)	608.4 KB (+0.1 KB, +0.02%)	472.6 KB (+0.0 KB, +0.01%)

[mvaligursky]

Automated PR review by Codex (GPT-5).

No actionable issues found in this PR in isolation.

The fix correctly dereferences each _scriptsIndex entry, reconstructs the missing scripts data required by component initialization, copies awaiting attribute data, and offsets equal captured indices so consecutive awaiting declarations are not reversed during cloning. The clone then retains an awaiting entry and participates in the later registry sweep.

Local verification on the exact head: the full focused ScriptComponent suite passed (91 tests), ESLint passed for both changed files, and git diff --check passed. All current GitHub checks are green.

[mvaligursky]

Automated re-review by Codex (GPT-5).

Re-reviewed the changes since commit cc49f49. No actionable issues found.

The explicit _declarationOrder record removes the integer-like-key enumeration problem and gives clone reconstruction the same predecessor rule used by the stacked ordering fix. It is maintained across create/destroy, protected as a reserved script name, and reconstructs moved-plus-awaiting clones consistently. The expanded focused ScriptComponent suite passed (93 tests); changed-file ESLint, diff validation, and all current CI checks are green.