Document Calendar ORC metadata limitation

[marcinsbd]

Description

The follow up of the #26507
It's related to the #26865

Additional context and related issues

Release notes

(x ) This is not user-visible or is docs only, and no release notes are required.
( ) Release notes are required. Please propose a release note for me.
( ) Release notes are required, with the following suggested text:

## Section
* Fix some things. ({issue}`issuenumber`)

Summary by Sourcery

Documentation:

• Note that Trino does not support Calendar entries in ORC file metadata and thus always treats dates and timestamps as Proleptic Gregorian, causing legacy data inconsistencies.

[sourcery-ai]

Reviewer's guide (collapsed on small PRs)

Reviewer's Guide

This PR enhances the ORC file-formats documentation by adding a known limitation about Trino’s ORC reader treating dates and timestamps using the Proleptic Gregorian Calendar due to missing calendar metadata support.

File-Level Changes

Change	Details	Files
Document ORC reader calendar metadata limitation	Add a 'Known limitations' section to file-formats.md Explain absence of Calendar entry support in ORC metadata Describe Proleptic Gregorian fallback and its impact on legacy dates/timestamps	docs/src/main/sphinx/object-storage/file-formats.md

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[sourcery-ai]

Hey there - I've reviewed your changes and they look great!

Prompt for AI Agents

Please address the comments from this code review:

## Individual Comments

### Comment 1
<location> `docs/src/main/sphinx/object-storage/file-formats.md:35` </location>
<code_context>
 configured.

+Known limitations:
+Currently, Trino does not support Calendar entry in Orc file metadata. As a results Trino always treats dates and timestamps as values written using Proleptic Gregorian Calendar. This causes incorrect reads of legacy dates and timestamps that were written using Hybrid Calendar.
+
 (parquet-format-configuration)=
</code_context>

<issue_to_address>
**issue (typo):** Typo: 'As a results' should be 'As a result'.

Please update the phrase for correct grammar.

```suggestion
Currently, Trino does not support Calendar entry in Orc file metadata. As a result Trino always treats dates and timestamps as values written using Proleptic Gregorian Calendar. This causes incorrect reads of legacy dates and timestamps that were written using Hybrid Calendar.
```
</issue_to_address>

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[marcinsbd]

@mosabua can you take a look?

[mosabua]

Suggested change

	proleptic Gregorian calendar. This causes incorrect values read when reading
	Gregorian calendar. This causes incorrect values when reading

[findepi]

• proleptic is an important word, we should keep it

• "This causes incorrect values when reading" reads as missing something.
  Incorrect values where? does the file gets broken, changed or malformed when we try to read it? or only the values reconstructed in computer memory are wrong?

[mosabua]

Suggested change

	date/time values before Oct 15, 1582 that were written using hybrid
	values before Oct 15, 1582 that were written using hybrid

[findepi]

we can remove "date/time", but then we need to indicate which types does this apply to.
@mosabua how would you want to indicate this?