Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Inline comments:
In `@DEVELOPMENT.md`:
- Around line 195-196: Add a single blank line immediately before the "#### API
Server" heading in DEVELOPMENT.md to satisfy markdown lint rule MD022; locate
the heading text "#### API Server" and insert one empty line above it so the
heading is separated from the previous paragraph.

In `@docs/contributor/api-server.md`:
- Around line 36-40: Update the architecture diagram reference that still points
to pkg/server/server.go so it instead points to the current server entry
pkg/server/serve.go; locate the diagram nodes (A, B, B1, C) in
docs/contributor/api-server.md and change the C node label or link that
currently shows "pkg/server/server.go" to "pkg/server/serve.go" (and verify the
B node arrow to C remains B1 --> C).

In `@pkg/collector/k8s/doc.go`:
- Around line 57-58: The doc example directly constructs k8s.Collector with
&k8s.Collector{}; change it to use the collector factory and functional options:
create a factory with collector.NewDefaultFactory(...) (passing required
dependencies/config), then obtain the collector via the factory (e.g.,
factory.NewCollector(ctx, /* functional options */) or factory.New(ctx, /*
options */) depending on the factory API) and use that instance instead of
&k8s.Collector{} to align with the collector.NewDefaultFactory and
functional-options pattern.

In `@pkg/collector/os/doc.go`:
- Around line 54-55: Replace the direct struct construction (&os.Collector{})
with the package factory pattern: call collector.NewDefaultFactory(...) to
obtain a factory configured with the appropriate functional options, then use
the factory to create the collector instance (e.g. factory.NewCollector(...) or
factory.Create(...)) and call Collect on that instance; update the example code
to show creating the factory (collector.NewDefaultFactory(...)), instantiating
the collector from it, handling errors, and then calling collector.Collect(ctx)
instead of using os.Collector directly.

In `@pkg/collector/systemd/doc.go`:
- Around line 35-41: Replace direct struct literals of systemd.Collector with
the factory/options pattern: stop creating instances via &systemd.Collector{...}
and instead obtain them through the collector factory (e.g.,
collector.NewDefaultFactory or the package's factory function) and pass service
names via the provided functional options; update both documented examples that
currently instantiate systemd.Collector directly to call the factory (e.g.,
collector.NewDefaultFactory(...) or systemd.NewWithOptions(...)) and supply
Services using the option helpers so the docs show the required collector
initialization contract.

In `@pkg/server/doc.go`:
- Around line 30-42: The documented middleware chain in pkg/server/doc.go is out
of order; update the comment to match the repository standard by listing
middleware in the order used by the server: metricsMiddleware →
versionMiddleware → requestIDMiddleware → panicRecoveryMiddleware →
rateLimitMiddleware → loggingMiddleware → handler (i.e., metrics, version,
requestID, panic, rateLimit, logging, then the actual handler), ensuring you
reference the exact middleware names (metricsMiddleware, versionMiddleware,
requestIDMiddleware, panicRecoveryMiddleware, rateLimitMiddleware,
loggingMiddleware) so docs and implementation guidance are aligned.

---

Outside diff comments:
In `@pkg/header/doc.go`:
- Line 100: Update the documentation bullet that currently reads "Created
timestamp" to use the new `metadata["timestamp"]` terminology so docs match the
header model; locate the validation bullet in pkg/header/doc.go referencing the
created timestamp and replace the phrase with either "timestamp" or explicitly
`metadata["timestamp"]` to reflect the updated header field naming.

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Duplicate comments:
In `@pkg/server/doc.go`:
- Around line 30-44: The doc comment lists middleware in the wrong order; update
the middleware chain description to match the repo standard ordering:
metricsMiddleware → versionMiddleware → requestIDMiddleware →
panicRecoveryMiddleware → rateLimitMiddleware → loggingMiddleware → (handler)
and ensure any surrounding entries like timeoutMiddleware and
bodyLimitMiddleware are placed consistently relative to that sequence; edit the
comment that mentions loggingMiddleware, panicRecoveryMiddleware, and
rateLimitMiddleware in pkg/server/doc.go so the list matches the exact
middleware symbol names (metricsMiddleware, versionMiddleware,
requestIDMiddleware, panicRecoveryMiddleware, rateLimitMiddleware,
loggingMiddleware) and reflects that they are applied outermost-to-innermost
before the handler.