Guard aura and unit classification reads against Midnight secret values, add an option to hide the Self Cast Key warning

[brconnell4]

Two independent changes, one commit each. Happy to split the second one into its own PR if you'd rather keep this to the bugfix.

1. fix: guard aura reads against Midnight secret values

On 12.0.0, Cell throws in any restricted context (PvP instance, encounter) as soon as a unit has a secret aura. Two errors on a solo frame, in sequence:

99x Cell/RaidFrames/UnitButton.lua:1753: attempt to perform boolean test on local 'isFullUpdate'
    (a secret boolean value, while execution tainted by 'Cell')

48x GetAuraSlots(): Auras cannot be accessed when secret while tainted by 'Cell'

Three distinct problems behind them:

updateInfo.isFullUpdate is itself secret. UnitButton_UpdateAuras branches on it directly. The rest of the payload is secret too (addedAuras and removedAuraInstanceIDs both come through as secret tables), so there is nothing readable in the incremental path. Now falls back to a full rescan whenever the flag can't be tested. Same fix in QuickAssist_UpdateAuras.

GetAuraSlots() doesn't return secrets, it refuses to run. This is the second error, and it's why fixing isFullUpdate alone isn't enough: the full-rescan path is exactly what's blocked. It affects ForEachAura in both UnitButton.lua and QuickAssist.lua, AuraUtil.ForEachAura in QuickCast.lua, and AuraUtil.FindAura behind F.FindAuraById. Each now runs protected and drops the pass rather than throwing. The UnitButton/QuickAssist helpers pass the varargs straight through, so there's no per-call table allocation on the hot path.

F.FindAuraById's predicate does idToFind == id, which throws on a secret spellId independent of the enumeration problem. Guarded with the existing F.IsValueNonSecret.

F.FindDebuffByIds / F.FindAuraByDebuffTypes already had an IsAuraRestricted() check, but Indicators/StatusIcon.lua:215 notes that check is unreliable, so they get the same backstop behind it.

Behaviour outside restricted contexts is unchanged. Inside them, aura indicators come up empty instead of erroring, which as far as I can tell is the ceiling for tainted code under the secret-aura rules rather than something more patching gets around. If there's a readable enumeration path I've missed I'd much rather use it than degrade.

2. fix: guard UnitIsCharmed against secret booleans

Same class of bug, found after the above. UnitIsCharmed returns a secret boolean for units under restricted control, so branching on it throws:

3x Cell/RaidFrames/UnitButton.lua:2907: attempt to perform boolean test on a secret
   boolean value (execution tainted by 'Cell')

Reproduced on a vehicle-seated party member. Two call sites, UnitButton_UpdateHealthColor and UnitButton_UpdateNameTextColor. Adds F.SafeBool alongside the existing F.IsValueNonSecret to flatten a possibly-secret boolean, defaulting a secret read to false, so a charmed unit falls through to vehicle/class coloring rather than the purple charm color.

The neighbouring UnitIsConnected / UnitIsPlayer / UnitInPartyIsAI reads in the same branch are not secret (they evaluate fine in the same frame that throws), and states.inVehicle is Cell's own true/nil, so those are left alone.

3. fix: guard the unit classification reads against secret booleans

UnitIsCharmed was not alone. UnitIsPlayer and UnitInPartyIsAI go secret the same way, and line 2866 tests all three, so it kept throwing after the previous commit:

45x Cell/RaidFrames/UnitButton.lua:2866: attempt to perform boolean test on a secret
    boolean value (execution tainted by 'Cell')

Rather than keep patching one call site per report, this covers every place the retail paths branch on them: UnitButton_UpdateHealthColor, UnitButton_UpdateNameTextColor, UnitButton_UpdateStatusText, UnitButton_UpdateName, the vehicle-root and preview-class checks, F.UnitFullName, F.GetUnitClassColor, F.UnitInGroup, F.GetTargetUnitID, F.GetTargetPetID, SpotlightFrame, StatusIcon, and BuffTracker.

Two helpers next to the existing F.IsValueNonSecret:

• F.IsPlayerUnit(unit, guid) falls back to the GUID prefix when UnitIsPlayer is secret. The GUID is readable in every context I've hit so far, so class coloring survives rather than degrading to NPC green. Most call sites already have a states.guid to hand it.
• F.IsAIUnit(unit) flattens UnitInPartyIsAI to false.

F.SafeBool now takes an explicit default, used for UnitInPhase in StatusIcon so a secret read doesn't paint a phasing icon on the whole group.

Both helpers are no-ops off Midnight and whenever the reads aren't actually secret, so nothing changes outside restricted contexts.

Also drops the NOTE in UnitButton_UpdateHealthColor claiming that path reads only non-secret data, which is what these reports disproved.

4. feat: add an option to hide the Self Cast Key conflict warning

CheckConflicts() runs on every Click Castings OnShow, so anyone who deliberately keeps a SELFCAST modifier bound gets the popup every single time they open the tab. Adds a "Hide Self Cast Key Warning" checkbox to General -> Misc that short-circuits it. Defaults to off, so nothing changes unless you tick it.

New strings use the L identity fallback, matching how the rest of the General tab strings are handled.

Testing

Against r279-beta on a 120005 client. All touched files parse clean under luac. Verified in game on the retail build that produced the tracebacks above: both errors gone, aura indicators still correct outside restricted content, and the Click Castings popup suppressed with the new option enabled.

[NeeRgY]

Hi @brconnell4
I'm afraid you won't get a response from Enderneko, just like many others haven't. I've tried writing to Enderneko several times without getting a reply...
If you'd like, feel free to check out my Cell fork or the official Discord, I'm very active there right now.
I'm currently working hard on a Cell fork and making sure everything runs smoothly for Retail, Classic, TBC, and MoP.
Some similar fixes to yours are already in my version, along with plenty of others.