Emit CellID from RRC SCell Info (order-independent of ML1)

[shark-fi]

Summary

Makes --cell-kv capture the CellID reliably. Previously a CellID only appeared when an RRC SCell Info packet had been cached before an ML1 serving measurement fired — the identity is joined onto the ML1 line. If the RRC packet arrived after, or the ML1 serving cadence was sparse, the CellID/TAC/PLMN never reached the output even though the modem logged the serving-cell identity. (A real Mudi/RM520 walk exported 1185 rows with 0 CellIDs for exactly this reason.)

Stacked on fgsect#150 (--cell-kv) — builds directly on its RRC↔ML1 identity join.

What changed

Identity capture is now order-independent:

• LTE parse_lte_ml1_scell_meas and the NR ML1 serving path cache the latest serving signal per radio ({earfcn/nrarfcn, pci, rsrp[/rsrq/rssi]}).
• parse_lte_rrc_cell_info / parse_nr_rrc_scell_info, under --cell-kv, emit their own cell=scell line carrying the full identity (plmn/mcc/mnc/tac/cid/band/bwmhz) joined to that cached signal — or nothing when no signal is cached yet (so no all-zero-metric line, which downstream ingest drops; the ML1 join then fills the next measurement instead).

Net: whenever the modem logs an RRC SCell Info and any ML1 serving measurement has occurred (in either order), a --cell-kv line with the CellID is produced.

Example (decoded from real capture vectors)

# RRC SCell Info arrives, ML1 signal already cached for the cell:
LTE: pci=77,earfcn=1825,...,tac=39701,cid=162580531,band=3,bwmhzdl=15,bwmhzul=15 rssi=-60.0,rsrp=-95.5,rsrq=-11.0
NR:  pci=669,earfcn=641760,...,tac=31017,cid=21248152064,band=78,bwmhzdl=90,bwmhzul=90 rssi=0,rsrp=-88.0,rsrq=0
# No ML1 signal cached yet -> emits "" (ML1 join covers it once a measurement arrives)

Tests

New TestCellIdFromRrc covers LTE/NR RRC→kv emission with a cached signal, the empty-when-no-signal case, and ML1 signal caching. Full suite: 98 passing.

Deployment note

The device-side SCAT bundle must include this (and fgsect#150) for the CellID to flow — an older on-device bundle predating the identity join will still export empty CellIDs regardless of this change.

🤖 Generated with Claude Code

[shark-fi]

Consolidated into fgsect#153 (single PR off master with --cell-kv, --meas-gsmtap, and this order-independent CellID emission). Closing here.