Task: Fix unsubstituted {nats_wire_format} placeholder in systemd unit generator

Services with a custom args_template (http.server, telemetry, ore.service, wt.service, all 5 compute.wrapper replicas) start successfully with the correct wire format from ORES_NATS_WIRE_FORMAT instead of crashing on the literal string '{nats_wire_format}'.

• _substitute_args() in systemd_generate.py substitutes \{nats_wire_format\} with ${ORES_NATS_WIRE_FORMAT}, matching the existing \{nats_url\}=/\{nats_prefix\}=/=\{nats_tls_args\}= substitutions.
• compass services start brings up all services with a custom args_template without a --nats-wire-format crash.

(Implementation strategy. Written when work starts; key decisions are distilled into the parent story's * Decisions at close, but the plan itself stays — it is the historical record of what we did.)

Manual QA scenarios (scaffolded via compass add test_scenario, run through the QA Validation Runner panel) that verify this task. Link new ones here as they're created; the scenario doc itself links back via its "Verifies task" field.

Root cause: _substitute_args() replaced \{nats_url\}, \{nats_prefix\}, and \{nats_tls_args\} but never \{nats_wire_format\}, even though every custom args_template row in controller_service_definitions_populate.sql includes --nats-wire-format \{nats_wire_format\} (the SQL's own comment already warns this is easy to forget). Added the missing substitution (\{nats_wire_format\} -> ${ORES_NATS_WIRE_FORMAT}), regenerated and redeployed the units (compass systemd generate, compass systemd deploy – 9 units updated, exactly the ones with custom templates), and restarted the previously-crashing services. All 23 compass-managed services now start and report active (compass services status). ores.wt.service separately crashes with a SIGSEGV unrelated to this fix – out of scope, not chased further.