docs: 1.60 update — fix fabricated content, add kill/platform/known-issues docs

- Rewrite configuration.md from the real CLI/env surface (the page documented
  ~10 agent flags, /etc/default/socktop-agent, and env vars that don't exist)
- Fix token docs: SOCKTOP_TOKEN env + URL query param; client -t is --tls-ca,
  not a token flag
- Rewrite agent-integration.md: requests are plain text (get_metrics, ...),
  not JSON; correct proto schema, real GPU/metrics fields, 1.60 additive
  fields (sampled_at_ms, timestamp_us, journal notice)
- Fix connector.md: real ConnectorConfig builder API, error variants,
  examples list; bump to 1.60
- Document the 1.60 process kill feature (usage/general + keyboard-mouse)
- TLS: document exact-match pinning semantics, cert rotation, key perms,
  upgrade-clients-first note; genericize profile example
- Agent service: journal access setup (systemd-journal group), packaged-
  service cert path, drop fake positional-port form, fix broken fences
- New pages: Platform Notes (Windows/macOS/RISC-V/Pi kernel tip, ARMv7
  --no-default-features) and Known Issues
- Fedora build prereqs: libdrm-devel + libdrm-amdgpu (closes socktop#35)
- Freshen intro (1.60, new demo apng, correct crates.io names, GitHub
  Releases link), quick-start, upgrading (order notes, stale-binary tip),
  zellij (remove invalid pane_template example)

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

docs/src/advanced/zellij.md

@@ -39,34 +39,17 @@ Run it:
 zellij --layout socktop-layout.kdl
 ```
 
+## Saved Layouts
+
+Layouts placed in `~/.config/zellij/layouts/` can be launched by name:
+
+```bash
+cp socktop-layout.kdl ~/.config/zellij/layouts/socktop-monitoring.kdl
+zellij --layout socktop-monitoring
+```
+
+The pane commands reference [connection profiles](../usage/connection-profiles.md) by name (`-P rpi-master`), so create the profiles first.
+
 ## More Info
 
 For detailed Zellij documentation, see [Zellij](https://zellij.dev/).
-
-Create `~/.config/zellij/layouts/socktop-monitoring.kdl`:
-
-```kdl
-layout {
-    pane_template name="socktop_pane" {
-        command "socktop"
-        args "-P" "{profile}"
-    }
-    
-    pane split_direction="vertical" {
-        pane split_direction="horizontal" {
-            socktop_pane profile="production-web"
-            socktop_pane profile="production-db"
-        }
-        pane split_direction="horizontal" {
-            socktop_pane profile="staging-web"
-            socktop_pane profile="staging-db"
-        }
-    }
-}
-```
-
-### Use the Layout
-
-```bash
-zellij --layout socktop-monitoring
-```