Word warnings and errors by what failed, not by the library or Java class

[clytras]

Warnings

The issue codes are unchanged; only the free-text messages change.

• CATALOG_INDEX_UNUSABLE (AccessSource): since Jackcess 5.0.3 this only appears for a damaged index, so it now reads "this database's catalog index is damaged (1 of 8 tables can't be looked up); the catalog was read by scanning it instead". The README row already described a damaged index, so it needed no change.
• UNSUPPORTED_COLUMN_TYPE (TableReader): "this column type (COMPLEX_TYPE) can't be decoded; its raw bytes are kept".

Errors that started with a Java class name

Every error now reads error: <what>: <reason>:

Where	Before	After
verify --jdbc-url, can't connect (JdbcOptions)	error: IOException: can't connect to <url>: <reason><advice>	error: <url>: can't connect: <reason><advice>
--jdbc-driver jar missing (JdbcOptions)	error: NoSuchFileException: <jar>: no such JDBC driver jar	error: <jar>: no such JDBC driver jar
--jdbc-driver jar with no matching driver (JdbcOptions)	error: IOException: <jar> has no JDBC driver for <url>	error: <jar>: no JDBC driver in it accepts <url>
Input or verify output missing (Main.requireFile)	error: NoSuchFileException: <file>: no such file	error: <file>: no such file
verify --jdbc-url, reading the database fails (VerifyCommand, MySqlVerifier)	error: IOException: reading the database failed: … or error: IOException: the database could not be read back: …	error: <url>: reading the database failed: …
verify of a SQLite output it can't read (SqliteVerifier)	error: IOException: the output could not be read back: …	error: <output>: the output could not be read back: …
SQLite output fails while it is written (SqliteWriter): an SQL error, PRAGMA integrity_check, or the foreign-key check	error: IOException: writing the SQLite output failed: … (and the same IOException: prefix on the other two)	error: <output>: SQLite could not write it: …, error: <output>: PRAGMA integrity_check failed: …, …
A --binary files name escaping its directory (BinaryFiles, can't happen)	error: IOException: the file name …	error: <output>: the file name …

How it works:

• Main.message prints a plain IOException's message as is. Our own messages now always start by naming what failed.
• A file-system error that has a reason is also printed as is, since its message is already <file>: <reason>. One without a reason gets the reason in words for the common cases: no such file, no permission, not a folder, already exists, folder not empty.
• OutputException.of puts a plain IOException raised while an output is built under that output's name.
• MySqlVerifier.verify now lets the SQLException through, so VerifyCommand names the URL.
• Other I/O errors keep their class name, because the class name is the only description they have. Non-I/O errors also keep it: those are bugs.

A damaged index found while checking relationships

Damaging the index of a relationship's parent table made convert end with error: table <name> failed: IOException: Unexpected order in index entries …. The index fails while the data is checked before writing: the relationship check looks parent keys up through it. That lookup doesn't go through RowStream, so the error wasn't a SourceException, and under --on-table-error fail TableFailure threw a plain IOException.

KeyLookup (and creating it in AccessSource.keyLookup) now wraps an IOException with SourceException.readFailed, as RowStream does. The error therefore reads like the others: error: <input>: reading table <name> failed (IOException: Unexpected order in index entries …); the file may be damaged: try Compact and Repair in Access. It is reported as TABLE_READ_FAILED with the same text. Unchecked exceptions pass through unchanged, so ParentKeys still falls back to scanning when Jackcess can't seek an index's collation.

A table that fails to be written under fail is still named after the output: error: <output>: table <name> failed: ….

• New tests in MainTest: a missing input, an unreachable --jdbc-url, a missing --jdbc-driver, and Main.message itself.
• AtomicOutputTest covers a plain error being put under the output's name.
• CatalogIndexTest now pins the whole new warning text.
• VerifyJdbcIT checks the new connection-error prefix against MySQL.
• The unsupportedFieldsV2007 golden file is updated.
• ConvertCommandTest.aDamagedIndexReadsLikeAnyDamagedTable damages the Customers primary-key index of the schema-fidelity fixture with a new DamagedCopy.withIndexDamaged helper. Without the fix it fails with the old error: table Customers failed: IOException: Unexpected order in index entries ….
• SqliteTableErrorTest.aWriteFailureUnderFailNamesTheOutput covers a write failure under fail.

./mvnw -B -ntp verify and ./mvnw -B -ntp verify -Pintegration both pass.