Show transceiver, ICE, SCTP and track state with their events, cut signaling-thread waits from getters

[MarshalX]

One-off script, 50 rounds, audio + video + 4 channels, medians, macOS arm64:

Metric	Before	After	Change
Renegotiation	6.01 ms	5.08 ms	-15%
transceiver.mid	9.83 µs	1.01 µs	-90%
sender.track	7.61 µs	4.72 µs	-38%
getSelectedCandidatePair()	19.5 µs	10.6 µs	-46%

getStats is unchanged

Also fixes remote data channels collected before their open event

[read-the-docs-community]

Documentation build overview

📚 wrtc | 🛠️ Build #35197095 | 📁 Comparing b7f2e59 against latest (8a2d7c0)

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2 files changed

+ search/index.html
± guides/connections/index.html