fix: RFC 2047 MIME encoding for non-ASCII email subjects

[bardusco]

Problem

When creating a draft or sending an email with non-ASCII characters in the subject (e.g., accented characters in Portuguese, French, German, etc.), Gmail displays garbled text.

Example:

• Input subject: Relatório de Comissões - Segunda Quinzena de Março
• Gmail displays: Relatório de Comissões - Segunda Quinzena de Março

Cause

The Subject header is set as plain UTF-8 text, but per RFC 2047, non-ASCII values in email headers must use MIME encoded-word syntax. The message body correctly uses Content-Type: text/plain; charset=UTF-8, but headers need their own encoding.

Fix

Added encodeHeaderValue() private method that applies RFC 2047 Base64 encoded-word syntax (=?UTF-8?B?...?=) only when non-ASCII characters are present. ASCII-only subjects are left unchanged. Applied to both createDraft() and sendEmail().

[bardusco]

Problem

When creating a draft or sending an email with non-ASCII characters in the subject (e.g., accented characters in Portuguese, French, German, etc.), Gmail displays garbled text.

Example:

• Input subject: Relatório de Comissões - Segunda Quinzena de Março
• Gmail displays: Relatório de Comissões - Segunda Quinzena de Março

Cause

The Subject header is set as plain UTF-8 text, but per RFC 2047, non-ASCII values in email headers must use MIME encoded-word syntax. The message body correctly uses Content-Type: text/plain; charset=UTF-8, but headers need their own encoding.

Fix

Added encodeHeaderValue() private method that applies RFC 2047 Base64 encoded-word syntax (=?UTF-8?B?...?=) only when non-ASCII characters are present. ASCII-only subjects are left unchanged. Applied to both createDraft() and sendEmail().

[bardusco]

Problem

When creating a draft or sending an email with non-ASCII characters in the subject (e.g., accented characters in Portuguese, French, German, etc.), Gmail displays garbled text.

Example:

• Input subject: Relatório de Comissões - Segunda Quinzena de Março
• Gmail displays: Relatório de Comissões - Segunda Quinzena de Março

Cause

The Subject header is set as plain UTF-8 text, but per RFC 2047, non-ASCII values in email headers must use MIME encoded-word syntax. The message body correctly uses Content-Type: text/plain; charset=UTF-8, but headers need their own encoding.

Fix

Added encodeHeaderValue() private method that applies RFC 2047 Base64 encoded-word syntax (=?UTF-8?B?...?=) only when non-ASCII characters are present. ASCII-only subjects are left unchanged. Applied to both createDraft() and sendEmail().

[bardusco]

Problem

When creating a draft or sending an email with non-ASCII characters in the subject (e.g., accented characters in Portuguese, French, German, etc.), Gmail displays garbled text.

Example:

• Input subject: Relatório de Comissões - Segunda Quinzena de Março
• Gmail displays: Relatório de Comissões - Segunda Quinzena de Março

Cause

The Subject header is set as plain UTF-8 text, but per RFC 2047, non-ASCII values in email headers must use MIME encoded-word syntax. The message body correctly uses Content-Type: text/plain; charset=UTF-8, but headers need their own encoding.

Fix

Added encodeHeaderValue() private method that applies RFC 2047 Base64 encoded-word syntax (=?UTF-8?B?...?=) only when non-ASCII characters are present. ASCII-only subjects are left unchanged. Applied to both createDraft() and sendEmail().

[bardusco]

Problem

When creating a draft or sending an email with non-ASCII characters in the subject (e.g., accented characters in Portuguese, French, German, etc.), Gmail displays garbled text.

Example:

• Input subject: Relatório de Comissões - Segunda Quinzena de Março
• Gmail displays: Relatório de Comissões - Segunda Quinzena de Março

Cause

The Subject header is set as plain UTF-8 text, but per RFC 2047, non-ASCII values in email headers must use MIME encoded-word syntax. The message body correctly uses Content-Type: text/plain; charset=UTF-8, but headers need their own encoding.

Fix

Added encodeHeaderValue() private method that applies RFC 2047 Base64 encoded-word syntax (=?UTF-8?B?...?=) only when non-ASCII characters are present. ASCII-only subjects are left unchanged. Applied to both createDraft() and sendEmail().

[bardusco]

Problem

When creating a draft or sending an email with non-ASCII characters in the subject (e.g., accented characters in Portuguese, French, German, etc.), Gmail displays garbled text.

Example:

• Input subject: Relatório de Comissões - Segunda Quinzena de Março
• Gmail displays: Relatório de Comissões - Segunda Quinzena de Março

Cause

The Subject header is set as plain UTF-8 text, but per RFC 2047, non-ASCII values in email headers must use MIME encoded-word syntax. The message body correctly uses Content-Type: text/plain; charset=UTF-8, but headers need their own encoding.

Fix

Added encodeHeaderValue() private method that applies RFC 2047 Base64 encoded-word syntax (=?UTF-8?B?...?=) only when non-ASCII characters are present. ASCII-only subjects are left unchanged. Applied to both createDraft() and sendEmail().

[bardusco]

Problem

When creating a draft or sending an email with non-ASCII characters in the subject (e.g., accented characters in Portuguese, French, German, etc.), Gmail displays garbled text.

Example:

• Input subject: Relatório de Comissões - Segunda Quinzena de Março
• Gmail displays: Relatório de Comissões - Segunda Quinzena de Março

Cause

The Subject header is set as plain UTF-8 text, but per RFC 2047, non-ASCII values in email headers must use MIME encoded-word syntax. The message body correctly uses Content-Type: text/plain; charset=UTF-8, but headers need their own encoding.

Fix

Added encodeHeaderValue() private method that applies RFC 2047 Base64 encoded-word syntax (=?UTF-8?B?...?=) only when non-ASCII characters are present. ASCII-only subjects are left unchanged. Applied to both createDraft() and sendEmail().

[bardusco]

Problem

When creating a draft or sending an email with non-ASCII characters in the subject (e.g., accented characters in Portuguese, French, German, etc.), Gmail displays garbled text.

Example:

• Input subject: Relatório de Comissões - Segunda Quinzena de Março
• Gmail displays: Relatório de Comissões - Segunda Quinzena de Março

Cause

The Subject header is set as plain UTF-8 text, but per RFC 2047, non-ASCII values in email headers must use MIME encoded-word syntax. The message body correctly uses Content-Type: text/plain; charset=UTF-8, but headers need their own encoding.

Fix

Added encodeHeaderValue() private method that applies RFC 2047 Base64 encoded-word syntax (=?UTF-8?B?...?=) only when non-ASCII characters are present. ASCII-only subjects are left unchanged. Applied to both createDraft() and sendEmail().