chore(rmi-backend): apply fleet-template standards — add .editorconfig + .gitattributes, fix stale IPs, tighten qdrant-audit CI gate

- Add .editorconfig (Python 4-space, default 2, LF, UTF-8) per fleet-template
- Add .gitattributes (LF normalization, lockfile binary, generated paths)
- Fix AGENTS.md:35 — netcup (100.100.18.18) → Talos (100.104.130.92)
- Mark TODO.md:5 done — Qdrant stale IP (fixed in 3c6b295)
- Remove continue-on-error: true from qdrant-cleanup job (inner step has || \, no behavior change)

Refs: standards/GAPS.md#4 (Make CI gates authoritative), standards/GAPS.md#9 (Repo tooling parity), standards/GAPS.md#12 (Documentation contradictions)

.editorconfig

@@ -0,0 +1,20 @@
+root = true
+
+[*]
+charset = utf-8
+end_of_line = lf
+indent_style = space
+indent_size = 2
+insert_final_newline = true
+trim_trailing_whitespace = true
+max_line_length = 100
+
+[*.md]
+trim_trailing_whitespace = false
+
+[Makefile]
+indent_style = tab
+
+[*.{py,pyi}]
+indent_size = 4
+max_line_length = 120