fix(windows): clippy/build cleanups the on-glass build surfaced (-D warnings)

Built the host crate (`cargo clippy --features nvenc -D warnings`) and the driver
workspace (`cargo build`) on the RTX box — the project's intended Windows gate,
which `cargo check` (what the goal1/§2.5 work used) never runs. It surfaced lint
issues accumulated across the goal1 / §2.5 / this-session Windows work:

- 9× redundant `as *mut c_void` after `.as_raw_handle()` (already `*mut c_void`):
  idd_push.rs (3, this session), service.rs (3, this session), manager.rs (3,
  pre-existing §2.5 — my OwnedHandle work copied the idiom). Removed the casts +
  the now-unused `use std::ffi::c_void` in idd_push.rs / manager.rs (service still
  uses it).
- `if_same_then_else` in session_plan.rs::resolve_topology (pre-existing goal1
  stage 3): collapsed the two `false` arms into one condition (behavior identical).
- `unused_unsafe` in the driver `pod_init!` macro: it expands at call sites already
  inside an `unsafe` block, where its own `unsafe` is redundant — `#[allow(
  unused_unsafe)]` (needed at the non-unsafe sites, redundant at the nested ones).

After these, BOTH builds are clean on the box — validating the whole session's
blind Windows + driver work compiles + passes clippy on real hardware.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

crates/punktfunk-host/src/capture/windows/idd_push.rs

@@ -14,7 +14,6 @@ use super::dxgi::{make_device, D3d11Frame, HdrConverter, WinCaptureTarget};
 use super::{CapturedFrame, Capturer, FramePayload, PixelFormat};
 use anyhow::{bail, Context, Result};
 use pf_driver_proto::frame;
-use std::ffi::c_void;
 use std::os::windows::io::{AsRawHandle, FromRawHandle, OwnedHandle};
 use std::sync::atomic::{AtomicU32, AtomicU64, Ordering};
 use std::time::{Duration, Instant, SystemTime, UNIX_EPOCH};
@@ -400,7 +399,7 @@ impl IddPushCapturer {
             // Own the mapping handle so it (and its view) free via `MappedSection` RAII even on bail.
             let map = OwnedHandle::from_raw_handle(map.0 as _);
             let view = MapViewOfFile(
-                HANDLE(map.as_raw_handle() as *mut c_void),
+                HANDLE(map.as_raw_handle()),
                 FILE_MAP_ALL_ACCESS,
                 0,
                 0,
@@ -450,7 +449,7 @@ impl IddPushCapturer {
                     // Own the mapping handle so it (and its view) free via `MappedSection` RAII.
                     let dm = OwnedHandle::from_raw_handle(dm.0 as _);
                     let dv = MapViewOfFile(
-                        HANDLE(dm.as_raw_handle() as *mut c_void),
+                        HANDLE(dm.as_raw_handle()),
                         FILE_MAP_ALL_ACCESS,
                         0,
                         0,
@@ -936,9 +935,7 @@ impl Capturer for IddPushCapturer {
     fn next_frame(&mut self) -> Result<CapturedFrame> {
         let deadline = Instant::now() + Duration::from_secs(20);
         loop {
-            let _ = unsafe {
-                WaitForSingleObject(HANDLE(self.event.as_raw_handle() as *mut c_void), 16)
-            };
+            let _ = unsafe { WaitForSingleObject(HANDLE(self.event.as_raw_handle()), 16) };
             if let Some(f) = self.try_consume()? {
                 return Ok(f);
             }