Decode declared EPICS DBR_CHAR waveforms as text

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Summary

• EPICS gives a char waveform holding a NUL-terminated string (tomoscan's ScanStatus, FileName, FilePath, FullFileName) and one holding raw bytes (an NTNDArray image) the same wire type, so EpicsCaControlPort could only ever unpack it as an integer tuple.
• A deployment now declares which addresses on a route actually carry text via ControlPortRoute.text_addresses; declared addresses decode to Measurement(kind="Scalar", value=<str>), everything else is unaffected.
• Needed to read 2-BM's tomoscan status/filename PVs at all, ahead of wiring an observer for them.
• Guards element_count > 1 so the declaration stays inert (rather than raising) against a length-1 char waveform, which aioca collapses to a non-iterable scalar type — caught by code review before commit and covered by a regression test.

Test plan

• pytest tests/unit/operation/test_control_port_config.py tests/integration/test_epics_ca_control_port.py — 47 passed
• pytest tests/integration/test_caproto_control_port.py tests/integration/test_epics_pva_control_port.py — confirms the shared soft-IOC db addition doesn't disturb sibling adapters
• pytest tests/architecture — 30408 passed, 621 skipped
• ruff check / ruff format / pyright / tach check all clean
• naming review (R1-R6) on text_addresses — no violations
• code review — one finding (scalar DBR_CHAR crash), fixed, verified against a live soft IOC

🤖 Generated with Claude Code

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Coverage report

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File	Statements	Missing	Coverage	Coverage (new stmts)	Lines missing
apps/api/src/cora/infrastructure
control_port_route.py
apps/api/src/cora/operation/adapters
control_port_config.py
epics_ca_control_port.py					507
Project Total

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