Stop documenting the recovery API that 1.6.0 deleted

Disc::sweep, Disc::patch, Disc::copy, SweepOptions and PatchOptions have
zero occurrences in src/ — recovery moved to freemkv-engine — but they were
still documented in 30 places across README.md, TROUBLESHOOTING.md, six
files under docs/, seven src/ doc comments and a Cargo.toml comment.
README.md is the crate's GitHub front page and carried a full multi-pass
code example that cannot compile.

Two of the src/ references were intra-doc LINKS to deleted items
([`disc::Disc::copy`], [`disc::Disc::patch`] in scsi/mod.rs). They produced
no warning on a normal `cargo doc` only because they sit on pub(crate)
items; `--document-private-items` reports both, and they are gone now.

The README example is deleted rather than rewritten against the engine's
API: libfreemkv documenting a downstream crate's API on its own front page
is the drift that produced this, and it cannot even depend on it. The src/
references become plain code spans naming freemkv_engine::recovery::* —
deliberately not links, for the same reason.

docs/rip-recovery.md was 202 lines about relocated code. It now documents
only what this crate owns — Drive::read, SenseFamily, DiscStream's adaptive
batch halving — plus the read-path design constraints, which belong with the
code that enforces them, and points at freemkv-engine/src/recovery/ for the
strategy. api-design.md's module tree is regenerated from the real src/disc/
and src/drive/ layouts instead of hand-patched; it had listed sweep.rs,
patch.rs, mapfile.rs and read_error.rs, none of which exist.

Three stale facts surfaced while rewriting and are corrected: the read
timeouts are 10 s / 60 s, not the documented 1.5 s / 30 s; Drive::reset and
SgIoTransport::reset no longer exist at all, so "no SCSI reset from any read
path" is now stated as the stronger fact it has become; and verify_title,
listed as a progress-emitting operation, was removed entirely.

CHANGELOG.md keeps its references — those are the historical record of the
releases that shipped the API.

src/scsi/mod.rs

@@ -44,7 +44,7 @@ pub const AACS_KEY_CLASS: u8 = 0x02;
 pub(crate) const TUR_TIMEOUT_MS: u32 = 5_000;
 
 /// Timeout for content READ commands (READ_10 / READ_12) on the fast
-/// path — the [`disc::Disc::copy`] sweep that bisects-on-failure.
+/// path — the `freemkv_engine::recovery::copy` sweep that bisects-on-failure.
 ///
 /// 10 s is calibrated from live empirical data on an LG BU40N + Initio
 /// 1618L bridge ripping a UHD with marginal sectors:
@@ -67,7 +67,7 @@ pub(crate) const TUR_TIMEOUT_MS: u32 = 5_000;
 pub(crate) const READ_TIMEOUT_MS: u32 = 10_000;
 
 /// Timeout for content READ commands on the recovery path —
-/// [`disc::Disc::patch`]'s targeted retries on bad ranges. Matches
+/// `freemkv_engine::recovery::patch`'s targeted retries on bad ranges. Matches
 /// `sg_dd`'s 60 s ceiling: long enough that any sector the drive can
 /// recover at all gets the time to do so, short enough that an
 /// unresponsive bus is detected before the per-range watchdog fires.
@@ -77,7 +77,7 @@ pub(crate) const READ_TIMEOUT_MS: u32 = 10_000;
 /// safety ceiling, not a steady-state cost.
 ///
 /// Historical note (2026-05-08): briefly lowered to 2 s with a 5×
-/// inline retry loop in `Disc::patch` to mimic the kernel `sr_mod`
+/// inline retry loop in `freemkv_engine::recovery::patch` to mimic the kernel `sr_mod`
 /// driver's auto-retry pattern. The synthetic logic worked but on the
 /// live drive each "2 s" read paid ~1.5 s of kernel SCSI mid-layer
 /// error escalation on top, so 5× retries took ~17 s per LBA and
@@ -237,7 +237,7 @@ impl ScsiSense {
     ///
     /// `false` for HARDWARE ERROR, DATA PROTECT, UNIT ATTENTION,
     /// ILLEGAL REQUEST, BLANK CHECK, and any unknown key. Used
-    /// by [`Error::is_marginal_read`] / `Disc::copy`'s hysteresis
+    /// by [`Error::is_marginal_read`] / `freemkv_engine::recovery::copy`'s hysteresis
     /// dispatch.
     pub fn is_marginal(&self) -> bool {
         matches!(
@@ -1022,8 +1022,8 @@ mod parse_sense_tests {
 #[cfg(test)]
 mod scsi_sense_predicate_tests {
     //! Classification of [`ScsiSense`] predicate methods against SPC-4
-    //! §4.5.6 Table 28 sense keys. These drive `Disc::copy` hysteresis
-    //! and `Disc::patch` routing; a misclassification here silently
+    //! §4.5.6 Table 28 sense keys. These drive `freemkv_engine::recovery::copy` hysteresis
+    //! and `freemkv_engine::recovery::patch` routing; a misclassification here silently
     //! changes which sectors get retried vs. marked unreadable.
     use super::*;