Match .gitignore, .editorconfig and .golangci.yml to sneak/prompts (closes #174)

REPO_POLICIES.md asks for the standard .gitignore and .editorconfig
followed by the repository's own entries, and for the canonical
.golangci.yml. The shared parts and .golangci.yml now match the
sneak/prompts copies at 065357920a0a09bd736bf33d4cb5ce935fdc2328 byte
for byte. .editorconfig has no entries of its own left, since the
standard file now carries the [*.go] section. .golangci.yml disables
canonicalheader, as the canonical copy does.

Model: opus-5-5

.editorconfig

@@ -11,7 +11,8 @@ insert_final_newline = true
 [Makefile]
 indent_style = tab
 
-# This repository's own entries, after the shared content above.
-
 [*.go]
 indent_style = tab
+
+# This repository's own sections, such as one for another language it
+# uses, go below this comment, and a re-vendor keeps them.

.gitignore

@@ -27,7 +27,7 @@ node_modules/
 # Environment files. `*.env` covers bare `.env` and the `prod.env`
 # convention. Only the templates `example.env` and `sample.env` are
 # re-included below. A repository that commits any other template adds
-# its own negation after these lines, for example `!.env.example`.
+# its own negation at the end of this file, for example `!.env.example`.
 *.[eE][nN][vV]
 .[eE][nN][vV].*
 .[eE][nN][vV][rR][cC]
@@ -46,7 +46,9 @@ node_modules/
 [iI][dD]_[eE][dD]25519
 [iI][dD]_[eE][dD]25519_[sS][kK]
 
-# This repository's own entries, after the shared content above.
+# This repository's own entries, such as its build outputs, go below
+# this comment, and a re-vendor keeps them. Anchor a binary built at the
+# root: `/myapp`, never `myapp`, which also ignores `cmd/myapp/`.
 
 # Build output
 dist/

.golangci.yml

@@ -25,6 +25,8 @@ linters:
     # silenced by disabling that name, not by enabling the successor.
     - wsl              # Deprecated, replaced by wsl_v5
     - gomodguard       # Deprecated, replaced by gomodguard_v2
+    # Misses findings at random in v2.14.0; back once a pinned release fixes it
+    - canonicalheader
   settings:
     lll:
       line-length: 88

TODO.md

@@ -23,6 +23,13 @@ Run `make frontend-viewport-test` in CI as its own step; it is not part of
 
 # Completed Steps
 
+- 2026-10-19: `.gitignore`, `.editorconfig` and `.golangci.yml` are the
+  sneak/prompts copies at `0653579`
+  ([#174](https://git.eeqj.de/sneak/netwatch/issues/174)). `.gitignore` is the
+  standard file followed by this repository's own entries; `.editorconfig` is
+  the standard file alone, which now carries the `[*.go]` section.
+  `.golangci.yml` disables `canonicalheader`, as the canonical copy does,
+  because golangci-lint v2.14.0 misses its findings at random
 - 2026-10-19: `package.json` has no `version` field and is marked
   `"private": true` ([#158](https://git.eeqj.de/sneak/netwatch/issues/158)). It
   said `1.0.0`, a release that has not been made, and nothing read it; the git