Switch to telemetry deck

[ActuallyTaylor]

What does this change?

This PR changes our telemetry provider from PostHog to telemetry deck. PostHog was proving to be incredibly difficult to get accurate analytics from.

How was it tested?

TelemetryDeck was setup and I waited for signals to show up in the app.

[ActuallyTaylor]

@claude

[claude]

Claude finished @ActuallyTaylor's task in 1m 34s —— View job

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Claude finished the review

Todo list:

• Gather context (PR diff, changed files)
• Read changed files in detail
• Review for correctness, security, and consistency issues
• Post review feedback

Summary

The trigger comment was just @claude with no specific request, so I did a code review of this PR (PostHog → TelemetryDeck migration). Overall the migration is clean and consistent — no leftover PostHog references, config/plist/README are updated in tandem, and the opt-in-when-blank behavior is preserved.

Findings

1. Likely accidental/stray project reference — Minna.xcodeproj/project.pbxproj
A PBXFileReference for AudioEngine was added and inserted into the Packages group, but there's no corresponding PBXBuildFile, XCSwiftPackageProductDependency, or XCRemoteSwiftPackageReference for it, and there's no AudioEngine directory anywhere in the repo:

Minna.xcodeproj/project.pbxproj:96:  DBFCD235303F465100A99DC6 /* AudioEngine */ = {isa = PBXFileReference; lastKnownFileType = wrapper; path = AudioEngine; sourceTree = "<group>"; };
Minna.xcodeproj/project.pbxproj:262:  DBFCD235303F465100A99DC6 /* AudioEngine */,

This looks unrelated to the TelemetryDeck migration and unrelated to Package.resolved (which only adds the TelemetryDeck swiftsdk pin, cleanly). It reads like a dangling reference that leaked in from local Xcode state on the author's machine — worth double-checking Xcode didn't leave a broken group entry.

Fix this →

2. Minor: CHANGELOG entry filed under the wrong heading
CHANGELOG.md line 12, "Moved to TelemetryDeck for private telemetry," is listed under ### Fixed, but this is a provider swap, not a fix. The file already has a ### Changed convention used elsewhere (e.g. lines 36, 119) that fits better here.

3. Nit: redundant line in Minna/IrisApp.swift:80-82

// Initialize the telemetry wrapper
_ = TelemetryWrapper.shared
TelemetryWrapper.shared.didLaunch()

TelemetryWrapper.shared.didLaunch() alone already triggers the lazy static let shared initialization, so the _ = TelemetryWrapper.shared line is unnecessary. Not a bug, just dead code.

4. Nit: signal name vs. identifier mismatch in Minna/TelemetryWrapper.swift:14

static let open = "didLaunch"

The Swift identifier is open but the actual signal string sent to TelemetryDeck is "didLaunch". Harmless, but a reader matching signal names in the TelemetryDeck dashboard back to code has to know .open → "didLaunch".

None of these block the migration — #1 is the only one I'd actually want addressed before merge (it looks like it doesn't belong in this diff at all); #2–#4 are optional polish.
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