feat: stabilize v0.3.0 public API bundle (#77)

* feat: stabilize v0.3.0 public API bundle

This commit aggregates the breaking and additive API changes that ship
together as v0.3.0. The individual PRs landed under chore: prefixes to
defer release-please from cutting an early version; this single feat:
commit with a BREAKING CHANGE: footer is the trigger for the v0.3.0
release PR.

Bundle contents (all merged to main):
- #70 (PR #71)  — Flat public Error enum + ergonomic constructors
                  workspace-wide
- #69 (PR #73)  — Transaction API consolidation (RAII guard recommended;
                  raw trio deprecated and #[doc(hidden)])
- #61 + #62
  (PR #74)      — FromRow modernization: #[derive(FromRow)] in new
                  hyperdb-api-derive crate, RowAccessor with cached
                  name->index lookup, breaking trait signature change,
                  blanket tuple impls deleted, #[hyperdb(rename)] and
                  #[hyperdb(index)] attributes
- #76           — Follow-ups A/B/C: typed io::Error sources in process.rs,
                  Error::InvalidOperation variant for caller misuse,
                  structured SQLSTATE on Cancelled/Closed/Connection

Follow-up D (flatten internal client::Error) deferred to v0.3.x as
issue #75 — internal-only, zero external consumers, larger than originally
scoped.

The code change in this commit is a small documentation refresh on the
crate-level rustdoc to (a) include hyperdb-api-derive in the companion
crates list and (b) fix a stale crate name (sea-query-hyper ->
sea-query-hyperdb). The body of the commit is the BREAKING CHANGE:
footer below; release-please uses it to generate the v0.3.0 entry in
CHANGELOG.md.

See MIGRATING-0.3.md for full migration recipes covering every breaking
change in the bundle.

BREAKING CHANGE: v0.3.0 reshapes the public hyperdb_api::Error enum
into a flat canonical structure (no Box<dyn StdError> cause channel,
no kind() method, no Other catch-all variant), and its constructor
surface (Error::new and Error::with_cause are deleted in favor of
domain-specific snake_case constructors). It also changes the FromRow
trait signature from fn from_row(row: &Row) to fn from_row(row:
RowAccessor<'_>), deletes the blanket 1/2/3/4-tuple FromRow impls,
deprecates Connection::begin_transaction/commit/rollback (use the RAII
guard at Connection::transaction() instead), introduces a new
Error::InvalidOperation variant, and changes Error::Cancelled and
Error::Closed from tuple to struct variants carrying structured
sqlstate. Every variant has a snake_case constructor; the FromRow
derive lives in a re-exported hyperdb-api-derive crate. See
MIGRATING-0.3.md for migration recipes.

* chore(ci): publish hyperdb-api-derive in release.yml + dry-run in ci.yml

Pre-release adversarial review of the v0.3.0 rollup CI/CD config caught
that hyperdb-api-derive (added in PR #74) was missing from release.yml's
publish-in-dependency-order step. hyperdb-api/Cargo.toml strictly pins
hyperdb-api-derive = "=0.X.Y", so cargo publish -p hyperdb-api would
fail at release time when crates.io can't resolve the strict version
of derive (because release.yml never published it).

Verified topologically:
- hyperdb-api-derive has zero workspace deps (only syn/quote/proc-macro2
  from the registry), so it can publish before any workspace crate.
- It's a runtime dep of hyperdb-api only.
- Inserted right after hyperdb-api-salesforce; existing order otherwise
  unchanged. Added a dependency-order comment to the publish step
  explaining the topology so future contributors don't break it.

Also adds hyperdb-api-derive to ci.yml's publish dry-run job. The
dry-run job exists exactly to catch this class of bug before release
time. Without this addition, the same blocker could re-emerge after a
future major-version refactor of derive.

Updates the stale "7 workspace-member version rows" comment in
release-please.yml to reflect the current 8-member workspace
(hyperdb-api-derive added in #74). The lockfile-sync sentinel
enumerates members at runtime via cargo metadata, so the count is
informational; correctness is unchanged.

Verified locally:
- cargo publish -p hyperdb-api-derive --dry-run: succeeds
- cargo publish -p sea-query-hyperdb --dry-run: succeeds
- cargo publish -p hyperdb-bootstrap --dry-run: succeeds
- cargo metadata workspace topology check: order in release.yml is
  consistent with non-dev deps across all 7 publishable crates.

Author: StefanSteiner

.github/workflows/ci.yml

@@ -201,7 +201,7 @@ jobs:
     # Catches Cargo.toml metadata regressions (missing license, bad
     # include paths, etc.) on the subset of crates that have no
     # workspace deps — those are the only ones `cargo publish --dry-run`
-    # can check before anything's on crates.io. The other 4 crates
+    # can check before anything's on crates.io. The other crates
     # (hyperdb-api-core, hyperdb-api-salesforce, hyperdb-api, hyperdb-mcp)
     # resolve their path+version deps against the live index, which can't
     # succeed until those deps are themselves published. (Note:
@@ -223,8 +223,9 @@ jobs:
           cache-key: publish-dry-run
           rustflags: ""
       - run: |
-          cargo publish -p hyperdb-bootstrap   --dry-run
-          cargo publish -p sea-query-hyperdb   --dry-run
+          cargo publish -p hyperdb-bootstrap     --dry-run
+          cargo publish -p sea-query-hyperdb     --dry-run
+          cargo publish -p hyperdb-api-derive    --dry-run
 
   deny:
     # Enforces license allowlist, advisory ignore list, and banned-source

.github/workflows/release-please.yml

@@ -119,12 +119,13 @@ jobs:
 
       # `cargo metadata --format-version=1` forces a lockfile
       # reconciliation pass against the current Cargo.tomls. Empirically
-      # validated on this workspace: it flips exactly the 7 workspace-
+      # validated on this workspace: it flips exactly the 8 workspace-
       # member version rows (hyperdb-api, hyperdb-api-core,
-      # hyperdb-api-node, hyperdb-api-salesforce, hyperdb-bootstrap,
-      # hyperdb-mcp, sea-query-hyperdb) and touches no external dep
-      # rows. The "Verify lockfile diff is workspace-only" sentinel
-      # below catches it if a future cargo version diverges.
+      # hyperdb-api-derive, hyperdb-api-node, hyperdb-api-salesforce,
+      # hyperdb-bootstrap, hyperdb-mcp, sea-query-hyperdb) and touches
+      # no external dep rows. The "Verify lockfile diff is workspace-
+      # only" sentinel below catches it if a future cargo version
+      # diverges.
       #
       # Why not `cargo generate-lockfile`: it does a full re-resolve
       # and bumps unrelated transitive deps to their latest semver

.github/workflows/release.yml

@@ -207,7 +207,18 @@ jobs:
             # window for small crates.
             sleep 45
           }
+          # Publish order is dependency-topological:
+          # - hyperdb-api-salesforce, hyperdb-api-derive: leaves (no
+          #   workspace deps).
+          # - hyperdb-api-core: depends on hyperdb-api-salesforce
+          #   (optional, via salesforce-auth feature).
+          # - hyperdb-api: depends on hyperdb-api-core AND
+          #   hyperdb-api-derive (=X.Y.Z strict pin → derive must be
+          #   on the index when hyperdb-api builds).
+          # - hyperdb-mcp, hyperdb-bootstrap, sea-query-hyperdb: depend
+          #   on hyperdb-api / hyperdb-api-core; publish last.
           publish hyperdb-api-salesforce
+          publish hyperdb-api-derive
           publish hyperdb-api-core
           publish hyperdb-api
           publish hyperdb-mcp

hyperdb-api/src/lib.rs

@@ -16,8 +16,9 @@
 //! - `hyperdb-api` — High-level API (this crate)
 //!
 //! Optional companion crates:
-//! - `sea-query-hyper` — `HyperDB` SQL dialect backend for `sea-query`
+//! - `sea-query-hyperdb` — `HyperDB` SQL dialect backend for `sea-query`
 //! - `hyperdb-api-salesforce` — Salesforce Data Cloud OAuth authentication
+//! - `hyperdb-api-derive` — Proc-macro `#[derive(FromRow)]` (re-exported by this crate)
 //!
 //! # Quick Start
 //!