fix: upgrade Nix PostgreSQL from 16 to 17

- Change postgresql_16 → postgresql_17 in shell.nix (17.10 available)
- Both postgis and timescaledb confirmed available for PG17
- Remove PG17-only transaction_timeout SET from structure.sql
  (dump was already PG17, now compatible with running server)
- Auto-reinit triggers on version file mismatch

nix/shell.nix

@@ -6,7 +6,7 @@
   # Elixir/Erlang
   elixir,
   # Databases and caches
-  postgresql_16,
+  postgresql_17,
   redis,
   # SNMP tools
   net-snmp,
@@ -27,7 +27,7 @@
 
 let
   # PostgreSQL with TimescaleDB and PostGIS extensions
-  pg = postgresql_16.withPackages (ps: [
+  pg = postgresql_17.withPackages (ps: [
     ps.timescaledb
     ps.postgis
   ]);

priv/repo/structure.sql

@@ -10,7 +10,6 @@
 SET statement_timeout = 0;
 SET lock_timeout = 0;
 SET idle_in_transaction_session_timeout = 0;
-SET transaction_timeout = 0;
 SET client_encoding = 'UTF8';
 SET standard_conforming_strings = on;
 SELECT pg_catalog.set_config('search_path', '', false);